Nevada Sen. John Ensign, facing an ethics investigation stemming from his affair with a campaign aide, will resign Friday, his office announced.
The senator's decision was met with a collective sigh of relief — and little surprise — in his home state, where Ensign's scandals have dominated headlines for nearly two years.
Ensign, a Republican, had announced in March that he would not seek a third term in 2012, saying he wanted to spare his family from an "exceptionally ugly" campaign.
His resignation with more than 20 months left in his term will spare him the possibility of prosecution by the Senate Ethics Committee, which in February named a special counsel to investigate his potential violations of ethics rules and federal law.
"I will not continue to subject my family, my constituents or the Senate to any further rounds of investigation, depositions, drawn-out proceedings or especially public hearings," Ensign said in a statement. "For my family and me, this continued personal cost is simply too great."
He also denied violating Senate rules or laws.
Ensign's constituents appeared grateful, if not gleeful.
"You could see the writing on the wall for him," said Eric James, 42, a Las Vegas insurance agent and registered Democrat.
James, who had stopped by North Las Vegas City Hall on Thursday, said he considered Ensign an "average" politician whose seat probably would have been safe if not for his travails.
"If you can't keep your house clean, it affects your credibility," James said. "He couldn't throw mud anymore."
Down the hall, GOP consultants Nathan Emens and David Gibbs welcomed the end of the Ensign era, although both described him as a "good guy."
Emens, 30, of Las Vegas said the senator and the investigations that dogged him had "cast a shadow" over the party, "even if everything was his doing."
His resignation, Gibbs said, was good for Nevada and good for the Republican Party in the state.
"It's over. It's done. That's the big thing — this is closure," said Gibbs, 54, of North Las Vegas.
Ensign will formally submit his resignation letter to Vice President Joe Biden, who also is president of the Senate, on Friday. It will take effect May 3, when the Senate is scheduled to return from recess.
Two members of Congress from Nevada, Democrat Shelley Berkley and Republican Dean Heller, have already entered the race to succeed Ensign. Nevada's new Republican governor, Brian Sandoval, could appoint Heller to Ensign's seat, giving him the advantage of incumbency in what both parties expect to be one of the premier 2012 races.
That would trigger a special election for Heller's 2nd Congressional District seat, which "tea party" supporter Sharron Angle has announced her intention to seek. She narrowly lost a Senate race to Majority Leader Harry Reid in 2010.
In a statement Thursday evening, Sandoval thanked Ensign for his service and did not tip his hand about whom he might appoint.
"A true fiscal conservative and always a fighter for the Silver State, Sen. Ensign deserves our thanks for the work he has done," Sandoval said.
Ensign acknowledged his affair with campaign aide Cynthia Hampton in 2009 after her husband, Douglas Hampton — another Ensign aide — threatened to go public.
The senator later acknowledged that his parents had paid the Hamptons $96,000 after Douglas Hampton left his job in the senator's office.
The Hamptons have suggested the payment was severance, but critics have termed it an improper campaign contribution that Ensign's parents made to their son. Ensign called the payment a gift to the Hamptons.
The Senate Ethics Committee opened an investigation in June 2009. This February, the committee named a special counsel to look into assertions that Ensign violated ethics rules and federal law in the aftermath of the affair.
With Ensign's resignation, the panel loses its authority to discipline him, but not its power to investigate his conduct. The committee could refer its findings to state or federal legal authorities if it found that laws might have been violated.
When asked in March whether his decision not to seek reelection was driven by the ethics investigation, Ensign said, "If I was concerned about that, I would resign."
Douglas Hampton was indicted last month on charges of violating federal conflict-of-interest laws by improperly lobbying Ensign's office within one year of leaving his job as a senior aide. He has pleaded not guilty.
The Justice Department investigation that led to Hampton's seven-count indictment also looked into whether Ensign had helped him secure the lobbying work. But the department said in December that no charges were being pursued against the senator.
Democrats hold a 53-47 majority in the Senate, counting the two independents who caucus with them. They see Nevada as one of their top opportunities to gain a seat.
State Democrats quickly turned their attention to Heller, criticizing his vote last week for a Republican budget plan that Democrats charge would "end Medicare as we know it."