Democrat Bill Owens led Conservative Doug Hoffman by about 4,000 votes late Tuesday in New York state's heavily Republican 23rd congressional district.

The Republican candidate, centrist Dede Scozzafava, withdrew Saturday and endorsed her Democratic opponent Sunday. She remained on the ballot.

With about 77 percent of the precincts reporting, Owens had 49 percent of the vote to 45 percent for Hoffman, The New York Times reported. Rob Ryan, a Hoffman spokesman, said 10,000 absentee votes also remained to be counted and results might not be final for several days.

"It's going to be a long night," he said.

Scozzafava had the backing of the local Republican establishment. But Hoffman, running as the candidate of New York's long-established Conservative Party, received the support of many Republican headliners, including former Alaska Gov. Sarah Palin, Minnesota Gov. Tim Pawlenty and former U.S. Sen. Fred Thompson.

John McHugh, who had represented the district since 2003, winning with more than 60 percent of the vote in every election, resigned after President Obama named him secretary of the army.