Updated: Feb. 2, 5:07 p.m.

Connecticut Republican Sam Caligiuri came about 8 points from upsetting Rep. Christopher Murphy (D) three months ago, but the 2010 challenger announced Tuesday that he will not run for Connecticut’s 5th district seat again.

The Republican Party’s midterm election successes persuaded Caligiuri not to seek the seat, he said. The seat will be open in 2012 because of Murphy’s Senate candidacy.

“It was a very tough decision because the fire in my belly is stronger than ever before,” he told Roll Call on Tuesday evening. “I decided to run in ’10 because we thought the direction of the country was so awful. … But the broader goal of bringing fiscal responsibility to Washington, I think, was achieved when we took over the House.

“I decided that, on balance, given the new Republican majority in Congress, it was more important to stick close to my family,” the lawyer said.

Despite Caligiuri’s decision, the National Republican Congressional Committee sees the open 5th district seat as a pickup opportunity.

A Republican, Rep. Nancy Johnson, held the seat as recently as 2006. Sen. John Kerry (D-Mass.) essentially tied President George W. Bush in the district in the 2004 presidential election, winning by roughly 1,000 votes. Four years later, Barack Obama earned 56 percent of the vote against GOP presidential nominee John McCain, in what was Obama’s weakest performance in any of Connecticut’s Congressional districts.

Potential Democratic candidates have yet to rise to the surface. Names to watch on the Republican side include Danbury Mayor Mark Boughton and 2010 GOP primary candidates Justin Bernier, a former Congressional aide, and Mark Greenberg, a wealthy real estate entrepreneur.

Caligiuri acknowledged that a Republican would have to run a nearly perfect race to win in Connecticut, a state in which Democrats control virtually every statewide office and all five House seats.

“That is a very, very winnable seat if we run a strong candidate,” Caligiuri said.

He offered advice to interested parties. “You’ve got to make sure you got the fire in the belly to get on the phones and raise money six to eight hours a day,” he said. “None of these candidates has a well-developed finance network. Since Nancy Johnson’s defeat in 2006, what had been her network completely disintegrated.”

He also pleaded with local Republicans to avoid a contentious primary, something that he said could have cost him the contest in 2010.