Here Are the Key Races That Are Still Too Close to Project

Voters in states across the nation handed Republicans control of the U.S. Senate on Election Day 2014, strengthened their majority control of the House of Representatives and also made a strong showing in gubernatorial races.

But several key contests remain undecided as of this morning, and may not be resolved for some time, even sparking talk of recounts in some states and districts. Here's a roundup of the races that have truly come down to the wire.

Virginia -- Senate

The Virginia Senate race between Sen. Mark Warner and Republican candidate Ed Gillespie was expected to be a bright spot in an otherwise bleak night for Democrats. But even one of the most favorable races for the president's party ended much tighter than anticipated, with a recount all but certain. As of this morning, Warner leads Gillespie by just 12,150 votes, or roughly half a percentage point of the electorate: 49.1 percent to 48.6.

The race was one of several where third-party candidates received single-digit support that could have decided the contest: Robert Sarvis, a Libertarian, received 2.5 percent of the vote. While the race was too close for ABC News to project a winner, Warner declared victory by midnight on Election Night. "It was a hard-fought race. It went a little longer than we thought," Warner told supporters. "I want to congratulate Ed Gillespie. He ran a hard fought campaign." Gillespie has not conceded, and can request a recount under Virginia law, as the difference between the two candidates is less than 1 percent of the total votes cast. Brian W. Schoeneman, Fairfax County Electoral Board secretary, said such a count is possible. "We're in recount territory," he said.

Warner's team said they do not envision the Virginia Senate race leading to a recount, but instead think it will be a victory for the incumbent Democrat.

"I don't see any basis for a recount or a contest at this point," Marc Elias, a lawyer for Warner's campaign and chair of the Perkins Coie political law practice, said in a conference call today. "12,000 votes is a close election, but it's not a recountable election."

Asked if Warner jumped the gun by declaring victory Tuesday night despite the fact that the race had yet to be project, Elias said no, adding "He won this election and he appropriately declared victory."

Alaska -- Senate

Polls closed early this morning, but the outcome of the Alaska Senate race could be unclear for days because of slow ballot-counting procedures in far-flung communities. First elected to the Senate the same year as Barack Obama won the presidency, Democratic Sen. Mark Begich is fighting to secure a second term in the U.S. Senate in a year when three of his Democratic colleagues lost their seats. He's opposed by Republican Dan Sullivan, the state's former attorney general and a lieutenant colonel in the U.S. Marine Corps. As of this morning, Sullivan leads Begich, 110,203 votes to 102,054.

Democrats are banking on their strong ground game in distant areas to help Begich keep his seat, but Republicans hope Sullivan's efforts to link Begich to Obama will help him win another seat for the GOP. Over the weekend, Sen. Ted Cruz and former GOP presidential nominee Mitt Romney swooped into the state to help Sullivan shore up support among the conservative base. With 100 percent of precincts reporting, Sullivan leads Begich by just over 8,000, votes, but the race has yet to be projected.

Arizona -- Second Congressional District

Possibly the most competitive House race this election between Democratic Rep. Ron Barber and Former Air Force Col. Martha McSally, a Republican, remains in play. As of this morning, the race is a 50 percent to 50 percent tie, with McSally holding a slim 36-vote lead. This race looked much like the duo's 2012 faceoff, which was similarly tossup-race tight, when the victor, Barber, was declared 12 days after Election Day. The congressman squeaked by with fewer than 2,500 votes more than McSally to win in that race. The race likely will not be called until a full count of all absentee and early voting ballots are complete, an arduous, meticulous task given how few votes separated the two in 2012.

California -- 52nd Congressional District

It still remains unknown whether scandal-stricken former San Diego City Councilman and openly gay Republican Carl DeMaio was able to beat incumbent Rep. Scott Peters after a House race marked by nasty attack ads, allegations of sexual assault, and a mysterious campaign headquarters break-in. The race is razor this this morning. DeMaio leads, slightly with 72,431 votes compared with Peters, who won 71,679 votes.

New York - 25th Congressional District

Democratic incumbent Rep. Louise Slaughter, first elected to congress in 1987 and currently vying for her 15th term, remains locked in a tight race with Republican challenger Mark Assini. Though Slaughter initially claimed victory - "it wasn't a landslide ... but we did win and we're happy about that," she said last night -- as of Wednesday morning, the contest remains too close to project, with Slaughter leading Assini by just over 500 votes, 93,053 to 92,471. Slaughter is the ranking Democrat on the powerful House Rules Committee.

ABC's Arlette Saenz, Ben Siegel, Ali Dukakis, John Parkinson, Erin Dooley, Alex Mallin and MaryAlice Parks contributed reporting.