Evan Vucci / AP

Sen. Michael Crapo, R-Idaho, center, followed by his wife Susan, arrives at Alexandria General District Court in Alexandria, Va., on Friday, Jan. 4.

Idaho Republican Sen. Michael Crapo will lose his license for a year after pleading guilty Friday to a misdemeanor drunken driving charge in a Virginia court. 

In exchange for his plea, prosecutors dropped a charge of failing to obey a traffic signal.

After the hearing, Crapo gave a statement outside the Alexandria City courthouse apologizing for his actions. The senator said he had been drinking vodka and tonic at home on the night of the offense, became restless, couldn't sleep and went out for a drive.

His Dec. 23 arrest stunned colleagues and constituents alike, not only because of his squeaky-clean image but also because he's Mormon and had said he didn’t

Crapo said the night of his arrest was the first time he had ever driven under the influence, but that he has, in the last year or so, imbibed

"As a lifelong member of the Church of Jesus Christ of Latter Day Saints, I have endeavored all my life to be an outstanding member,” Crapo said. "I will carry through on appropriate measures for forgiveness and repentance in my church." 

He had been driving for about 30 minutes when he realized he was in no condition to drive and started to return home, he said. It was then that he ran a red light and was pulled over. 

"I am grateful, truly grateful, that no one was injured," Crapo said.

The senator was stopped after a patrol officer saw his vehicle go through a red light. After failing field sobriety tests, he was arrested and “taken into custody without incident,” according to Alexandria police. He registered a blood alcohol level above the legal limit, police said.

After his plea, Crapo received a $250 fine and a 12-month suspension of his driver's license. He will also be required to complete an alcohol safety program. As long as he remains on good behavior, he will not have to serve a 180-day suspended jail sentence. 

"There was no refusal (to take sobriety tests), no accident, no injuries," Alexandria Police spokesman Jody Donaldson told The Associated Press at the time of Crapo's arrest.

Crapo has served in the Senate since 1998, where he has built a reputation as a staunch social and fiscal conservative. He is currently in his third term and won't have to run again until 2016.

Crapo said he felt like he owed people a full explanation of his behavior and took numerous questions outside the courthouse. 

He is from Idaho Falls, Idaho, and has five children with his wife, Susan.

NBC's Frank Thorp and The Associated Press contributed reporting.

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