ALBANY, N.Y. — A Democrat won a special congressional election in a heavily Republican district in northern New York by exploiting a battle between moderates and conservatives for control of the GOP.

With 88 percent of the precincts reporting early Wednesday, lawyer and retired Air Force Capt. Bill Owens defeated businessman Doug Hoffman, the Conservative Party candidate, 49 percent to 46 percent.

Dierdre Scozzafava, a moderate Republican, withdrew from the race Saturday under pressure from the party’s right wing because of her support of abortion rights and same-sex marriage. She still picked up 5 percent of the vote.

Hoffman conceded the race Wednesday.

Hoffman started at a distant third and was viewed as a spoiler at best, cutting away at Scozzafava and opening the door for Owens. But prominent Republicans such as former vice presidential candidate Sarah Palin and Minnesota Gov. Tim Pawlenty endorsed Hoffman instead of the party-picked Scozzafava.

Owens’ victory may signal renewed strength among Democrats, or at least reassure them of Republicans’ perceived weakness. The seat has been strongly Republican for decades. The outcome leaves Republicans holding only two seats in the state’s 29-seat congressional delegation. Republican John McHugh vacated the seat in September to become Army secretary.

“They’re in a civil war over the definition of their party,” said Paul Blank, a Democratic consultant. “And the extremists have won.”

Republicans will be sorting out their identity as the party tries to strike a balance between growing its ranks and preserving the values that set it apart from the Democratic Party.

“I think that the Republican Party is broad enough to handle many different candidates, but the fact is that I’m a commonsense conservative Republican — I am not a radical,” Hoffman said Monday. “The point is that Assemblywoman Scozzafava was not a moderate Republican. She was an ultraliberal Republican.”