Brennan Linsley / AP

People celebrate in a Denver bar after a local television station announced the passage of Colorado's marijuana amendment on Tuesday, Nov. 6, 2012.

Colorado’s governor has a message for those excited by the decriminalization of marijuana in his state: “Don’t break out the Cheetos.”

The reason is that marijuana is still a controlled substance under federal law, raising all sorts off issues for how Colorado and Washington, the other state where voters decriminalized the recreational use of marijuana Tuesday, will implement their initiatives.

“The voters have spoken and we have to respect their will,” Colorado Gov. John Hickenlooper (D) said after the vote. “This will be a complicated process, but we intend to follow through. That said, federal law still says marijuana is an illegal drug, so don’t break out the Cheetos or goldfish too quickly.”

In both states, adults aged 21 and older will be allowed to possess a small amount of marijuana, which will be sold in only state-licensed stores where it will be heavily taxed. For the most part, pot could not be consumed in public. In Colorado, the amendment also allows people to grow a few plants at home.

Dr. Kevin A. Sabet, former senior drug policy advisor to the Obama administration and director of the Drug Policy Institute at the University of Florida, suggests these results could portend a growing weed war between the feds and the states.

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“Once these states actually try to implement these laws, we will see an effort by the feds to shut it down,” Sabet said. “We can only guess now what exactly that would look like, but the recent U.S. attorney actions against medical marijuana portends an aggressive effort to stop state-sponsored growing and selling at the outset.” 

The texts of each initiative -- Amendment 64 in Colorado and Initiative Measure 502 in Washington -- make clear that the elimination of penalties for possessing up to an ounce of marijuana if you are 21 or older takes effect after 30 days, once the election results are certified. But the provisions allowing commercial production and sale of cannabis for recreational use require regulations that will be written during the next year in both states.

The Justice Department has so far declined to discuss how the initiatives might function under federal law. Late Tuesday, a spokesman said in an e-mail to NBC News that they were reviewing the Colorado initiative and had no immediate comment.

Sue Ogrocki / AP file

"Don't break out the Cheetos or gold fish too quickly," Colorado Gov. John Hickenlooper (D) said after the marijuana initiative was passed in the state Tuesday.

Obama has cracked down harder on medical marijuana than any president to come before him, argues Rob Kampia, the executive director of the Marijuana Policy Project. In the 17 states where medical marijuana is legal, U.S. attorneys have enlisted the Drug Enforcement Agency and the Internal Revenue Service to take down hundreds of pot shops in just a few short years, Reuters reported.

Three states weighed in on medical marijuana Tuesday with mixed results. Massachusetts voters approved an initiative allowing people to use marijuana for medicinal purposes. In Arkansas, a similar initiative failed. In Montana, voters approved a plan to revamp an existing medicinal marijuana law to make it more restrictive.

Former DEA Chief Peter Bensinger, an outspoken opponent of marijuana legalization, said legalization would lead to an increase in crime and threaten public safety.

“You’ll lose productivity, you’ll have accidents on the highway, you’ll have absenteeism, and you’ll really have a much more weakened society if you have widespread use of marijuana,” Bensinger said.

Still, proponents argue it’s about time pot was made legal and that the war on weed hasn't worked. 

“The violence associated with it has become greater, use rates have gone up, the respect toward law enforcement has gone down so the government isn’t achieving any of its stated goals," legalization advocate Allen St. Pierre said. 

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Marijuana-legalization backers believe they’re well schooled on all things leafy – from cannabis to political tea leaves. With pro-pot measures leading in recent polls in Washington and Colorado, proponents don’t foresee federal agents interceding in those states if voters approve the initiatives.

Their rationale: Two years ago, when California voters considered a similar proposal to legalize the adult possession of an ounce or less of pot, U.S. Attorney General Eric Holder publicly vowed the feds would continue to prosecute anyone in that state caught possessing marijuana — even if the law passed. It failed.

This year, in contrast, federal anti-drug authorities have repeatedly declined to discuss decriminalization proposals in three states — including a measure in Oregon that would end the prohibition of marijuana there. (That initiative trailed in recent polls.) The response routinely delivered by U.S. Department of Justice spokeswoman Allison Price, including in an e-mail to NBC News: “We are not going to speculate on the outcome of the various ballot initiatives in each of the states.”

“That, to me, is significant because they didn’t just copy and paste what they did and said in 2010. We feel pretty good about that,” said Alison Holcomb, campaign director for Washington’s Initiative 502, which seeks to regulate and tax marijuana production and distribution in that state. According to a poll released Thursday, Initiative 502 had the support of 55 percent of Washington voters.

But Dr. Kevin A. Sabet, former senior drug policy advisor to the Obama Administration and director of the Drug Policy Institute at the University of Florida, predicts a far different law-enforcement reality on the ground in Washington — as well as in Colorado, where Amendment 64 would allow the state to regulate marijuana as it does alcohol.

“Once these states actually try to implement these laws, we will see an effort by the feds to shut it down,” Sabet said.

Sabet’s vision of post-election pot realities in Washington and Colorado — where Amendment 64 has majority support, according to a recent poll — seems to suggest a possible weed war between the feds and the states.

“We can only guess now what exactly that would look like,” Sabet said. “But the recent U.S. Attorney actions against medical marijuana portends an aggressive effort to stop state-sponsored growing and selling at the outset.” (That includes, he said, letters sent by federal prosecutors last January to medical marijuana dispensaries in Colorado operating within 1,000 feet of schools, ordering those businesses to halt sales.)

“The question voters should be asking themselves,” Sabet said, “before voting on these initiatives is this: Is your right to buy pot from a store down the street worth the risk of increased teenage drug abuse, increased enforcement action by the feds, and increased problems like 'stoned driving?’ "

Whether a legal showdown is ignited or not, some state-legalization proponents see their measures as possible footholds in a march toward national marijuana decriminalization.

“Exactly 80 year ago, Colorado voters approved a ballot measure to appeal alcohol prohibition, and that came prior to it being repealed by the federal government,” said Mason Tvert, co-director of the Yes on 64 campaign in Colorado, a state that already regulates the sale of medical marijuana. “And it was the individual states taking that type of action that ultimately resulted in the federal (Prohibition) repeal.

“The same kind of thing is underway with marijuana,” he added. “Whether there’s going to be a critical mass, who knows?”

In Washington, Holcomb echoed that uncertainty: "I'm not sure how that’s going to play out.”

“It may be there’s going to some generational evolution on this. Medical marijuana was introduced in the mid-90s and we were still talking to a lot of people that were coming out of the ‘Reefer Madness’ era, who had a lot of fear. And (medical marijuana) was a really powerful way to help them see that marijuana is not this terribly scary thing that they had been told,” Holcomb said.

Indeed, the most recent poll on Colorado’s Amendment 64 found that 73 percent of state state’s residents who are under age 30 want pot legalized. At the same time, more than half of seniors are against decriminalizing marijuana.

Anti-drug watchdog Sabet, meanwhile, sides with most current political leaders — “the overwhelming majority of Congress (and) both major presidential candidates” — as well as the American Medical Association standing against the decriminalizing of marijuana: “I don't envision national legalization as a realistic possibility in the near future.”

“The state-level efforts could soon prove to be a tipping point for more aggressive legalization initiatives,” Sabet said. “However, there is a growing consensus within the medical and treatment community — who deal with the problems of marijuana use and addiction everyday — to reject both extreme prohibition and lax legalization. I think we'll end up with a policy that is more centrist, for example, not punishing people by barring them from a job for a past marijuana arrest, but also not allowing marijuana to be marketed and sold like alcohol or cigarettes.”

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Members of the armed forces face a unique set of logistical challenges when serving in other states or countries: many lack the ability to simply go to the DMV to renew their driver’s licenses, filing taxes can be complex and voting in elections can be even more confusing.

"It is critically important to ensure that every voter entitled to an absentee ballot is given every chance to receive one,” said John Conklin, a spokesman for the New York State Board of Elections.

According to the 2010 Post Election Survey Report to Congress, 85 percent of active duty military members were registered to vote, compared with 65 percent of the civilian voting age population. Due to the dilemmas associated with members of the military voting, approximately 120,000 active duty military personnel indicated they never received the absentee ballot they requested. 

Here’s a brief guide to the voting process as it relates to service men and women:

Why do states have different voting requirements?
The Constitution gives each state the right to determine the "time, place, and manner" of all elections, including federal elections. As a result, there is great variation from state to state.

“FVAP (Federal Voting Assistance Program) strongly supports the adoption of the Uniform Military and Overseas Voters Act (UMOVA) as offered by the interstate Uniform Law Commission,” said Defense Department spokeswoman Eileen Lainez.

“UMOVA sets uniform deadlines for receiving registration forms and ballot applications, and sets a minimum standard for electronic transmission of registration forms and blank ballots.”

Seven states — Colorado, North Dakota, Nevada, Utah, Oklahoma, North Carolina and Virginia — and the District of Columbia have adopted UMOVA. In Hawaii, the measure has passed the legislature and is awaiting the governor's signature.

Do I have to vote in my home of record’s election?
Short answer: no. But remember that a service member’s home of record and home of residence are two different things.

The home of record only applies to the state where a person physically entered the armed services and has nothing to do with where they reside, said Debi McGlothlin, the assistant installation voting officer at Kentucky’s Fort Campbell.

“You can live in Arizona but go on vacation to Minnesota and decide to join the army from there. The Army will hold your home of record to Minnesota, but your residency on your LES (Leave and Earnings Statement) is going to be Arizona.”

When in doubt, check your LES — the military version of a paystub. Then you’ll know what state you should be voting in.

How do I register to vote?
Service men and women should fill out Federal Post Card Application online, which serves as a voter registration form and an absentee ballot request. As part of this form, a “U.S. address for voting purposes” is required. This is your legal U.S. state of residence, as generally specified on your LES.

It can be more confusing for spouses and eligible dependents to determine their state of residence. A wife or husband won’t receive their own LES spelling that information out.

Family members and spouses should visit your post’s Installation Voter Assistance Office for help determining which state they should vote in.

You can also check individual state residency requirements online. 

FVAP.gov provides direct links to all 55 states and territories election websites where additional information is often available.

Can’t remember if you’re registered at another location?
After multiple moves it can be confusing to remember where you last registered to vote. If you think you registered at your home of record or another state you’ve lived in, there are multiple ways to check.

“FVAP.gov is the 2012 election resource for military service members and overseas citizens,” said Lainez of the Defense Department. “Everything service members need this election season is available.”

The site provides access to online registration and absentee ballot request systems, state-specific information and more.

Additionally, members of the military and their families can get direct contact information for more than 7,800 local election offices, including names, phone numbers, e-mail addresses and where they can check their prior voter registration status.

Am I an absentee voter?
You can vote absentee in local, state and federal elections if you are a U.S. citizen 18 years or older and are an active-duty service member (or dependent) and do not physically live in the state where you registered to vote.

In order to request to vote absentee it’s important to fill out the Federal Post Card Application.

FVAP recommends that voters register to vote and request an absentee ballot in January of each year, or at least 90 days before Election Day.

“The ability for overseas voters to receive their ballot via e-mail has placed the ballot in their hands much earlier in the process and helped alleviates the problem of ballots being mailed back too late to be counted,” said Conklin from the New York State Board of Elections. “For the 2010 election we had the highest number of voters take advantage of the e-mail system to receive their ballots.”  

Military members and their families can get additional help from nearly 10,000 assistance officers worldwide. Service members may locate a nearby Installation Voting Assistance Office here.

“It is absolutely vital to have as much information as possible available online especially for the military and overseas voting community who can't just pick up the phone and call and ask questions,” Conklin said.

I can’t guarantee the ballot will return in time, or it never arrived.
While the postal service system is dependable to fixed locations overseas, like South Korea or Germany, having the additional challenge of service members constantly relocating around Afghanistan and other hostile areas can mean lengthy delays in delivering mail.  

States and territories are required to mail ballots at least 45 days before an election. If you have not received your ballot 30 days before the election, contact your local election official.

You can also vote using the back-up Federal Write-In Absentee Ballot. But in order to be eligible to use this back-up ballot, you must be absent from your voting residence and have applied for a regular ballot before that state’s deadline or 30 days before the general election. Also, in order to choose this option you must not have received the original absentee ballot as requested.

If in doubt, contact your unit’s voting officer. Fort Campbell's McGlothlin said all units have a voting officer with them when they deploy who take the tools necessary — the hard copies of books and forms — along with them.

“They’re all educated and they’re all geared up to go, in their tough boxes, when they get on the plane,” she added.

Making your vote count
Unlike the employees of most companies, every eligible voter in the military and their family can vote for their actual commander in chief.

The men and women of our military are defending the interests of the United States all over the globe and a great deal of effort has been put forth to ensure they still have a voice at the ballot box on Election Day, McGlothlin said.  

“They fight for this right and they need to use it, it’s their voice that’s going to make their lives easier.”

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