Latest News

Scott P. Brown said on Friday that he had opted out of the Senate race in Massachusetts to fill the seat being vacated by John Kerry.

The decision leaves the Republicans without a candidate yet for the special election set for June 25, and it could leave the seat in Democratic hands.

Other potential Republican candidates had been waiting for a signal from Mr. Brown, who was seen as the strongest Republican, despite the loss of his Senate seat last year to Elizabeth Warren.

Mr. Brown spurned entreaties from the National Republican Senatorial Committee to use his statewide name recognition and popularity — and his leftover campaign treasury — to help the party gain a seat.

"I have received a lot of encouragement from friends and supporters to become a candidate, and my competitive instincts were leading in the same direction," he said in a statement.

"Even so, I was not at all certain that a third Senate campaign in less than four years, and the prospect of returning to a Congress even more partisan than the one I left, was really the best way for me to continue in public service at this time," he said. "And I know it's not the only way for me to advance the ideals and causes that matter most to me."

Mr. Brown first alerted The Boston Herald, which was strongly supportive of him during his last campaign, that he was not running.

"U are the first to know," Mr. Brown said in a text message to The Herald.

Mr. Brown has told friends that he is exhausted from the lengthy and hard-fought campaign against Ms. Warren. He may run instead for governor in 2014, but for now his departure leaves the Republicans without a boldface name to try to wrest the seat from the Democrats.

There has been speculation that William F. Weld, the former governor who recently moved back to Massachusetts from New York, might mount a challenge. But one person close to him said that Mr. Weld viewed himself as an executive personality, not a legislative personality, and he has done nothing to indicate an interest in the Senate.

Other Republicans starting to surface include Gabriel Gomez, a businessman and a former member of the Navy SEALs, and State Representative Daniel Winslow, a former district court judge who served in the administration of Mitt Romney.

Whoever does decide to run has just four weeks to gather 10,000 signatures to get on the ballot.

Meanwhile, two Democratic congressmen, Edward J. Markey and Stephen Lynch, are already battling it out for their party's nomination and will face off in a primary on April 30.

Mr. Lynch put out a statement on Friday saying: "I understand Scott Brown's decision. He has basically been campaigning nonstop for three years. It's perfectly understandable that he wouldn't want to undertake another campaign."