Updated

JUNEAU, Alaska -- Republican Joe Miller on Friday ended his legal fight over Alaska's U.S. Senate seat, conceding the race to his bitter rival, incumbent Sen. Lisa Murkowski.

Miller's decision, announced at a news conference in Anchorage, came one day after the state certified Murkowski as the winner.

Miller had the option of appealing a federal judge's ruling or formally contesting the election results. He believes he is right about the law but thinks it is "very unlikely" an appeals court would side with him. He said he had to accept "practical realities."

Three courts ruled against Miller, who argued the state's handling of the election and vote count for Murkowski, who ran as a write-in candidate, was not in line with the law.

Miller had not called Murkowski to congratulate her, said his spokesman, Randy DeSoto. To say that she'd won it fair and square, DeSoto said, "is not in his thinking."

Friday's announcement ends what started as a promising campaign for Miller, a Sarah Palin-backed tea party favorite who upset Murkowski in the GOP primary, in his first bid for statewide public office.

He was widely seen as the favorite for winning in the fall election. But then Murkowski re-emerged as a wild card, launching her longshot write-in campaign.

Miller's campaign began to unravel with revelations about his past and the handcuffing of a journalist by his security, which overshadowed his message of limited government and fiscal restraint. For example, there were disclosures that he and his family once received the types of government aid that he raised concerns about as a candidate. And personnel files from his time as an attorney for the Fairbanks North Star Borough showed that in 2008, he was disciplined after admitting he improperly used government computers for political purposes.

Miller insisted none of these things had anything to do with the campaign and instead were being used by his opponents to distract attention from the issues of the race.

In spite of all that, Miller retained strong support from his conservative base and won more than 35 percent of the vote in the November election. Results made official by the state Thursday showed Murkowski with a 10,252-vote lead over Miller, her closest opponent. Democrat Scott McAdams finished third.

On Friday, in front of supporters and with his wife at his side, Miller said his legal fight was a "worthy one," even though his motives and judgment were questioned.

The law calls for write-in ballots to have the ovals filled and either the candidate's last name or name as it appears on the declaration of candidacy written. Miller argued for a strict reading of this, meaning no ballots with misspellings or extra words should be counted, as the state did for Murkowski.

The state used discretion to determine voter intent, with officials saying they did not want to disenfranchise any voters. The state Supreme Court called voter intent "paramount," and refused to overturn election results favoring Murkowski.

A federal judge earlier this week acknowledged the law is "poorly drafted" but refused to second guess the high court.

Several state lawmakers have expressed interest in clarifying election law. The lieutenant governor also has vowed an internal review of the state's handling of the election.

Miller, a lawyer from Fairbanks, has insisted his fight was less about winning or losing and more about ensuring the integrity of the election process.

But Murkowski questioned Miller's motives and called on him to concede. In a statement Friday, she said she was glad he had "bowed to the rulings of the Alaska courts."