With Republican Bob Corker projected to win the Tennessee Senate race and Republican Sen. Jon Kyl the projected winner of the Arizona Senate race, obtaining a Senate majority became a steeper uphill battle for Democrats; they needed to sweep every remaining race.
Missouri Sen. Jim Talent was estimated to have been defeated by his Democratic opponent, Claire McCaskill, a former attorney and Jackson County prosecutor.
Hours after polls closed across the country, two races definied themselves as cliffhangers, with numbers so close news outlets would not project winners.
With nearly all precincts counted and the two candidates separated by a razor-thin margin, Virginians — and the nation — waited to see what would happen. The race is so close that it seems likely to be decided by absentee ballots. More than 130,000 absentee ballots were requested, but those votes have not been counted in three mostly suburban counties, as well as in the city of Alexandria, the Washington Post reports.
Numbers are also close in Montana, where Republican Sen. Conrad Burns had been struggling. Recent polls have been inconclusive, either showing Burns and Democrat Jim Tester tied or Tester with a 9-point lead.
In the battle for Maryland's open Senate seat, Democrat Ben Cardin, a U.S. Representative who's been in public office since 1967, was the projected winner over Republican Lt. Gov. Michael Steele.
In Rhode Island, Republican Sen. Lincoln Chafee was unseated by Democratic challenger Sheldon Whitehouse, CBS News estimates. And in Ohio, seven-term Democratic Rep. Sherrod Brown edged out GOP Sen. Mike DeWine. The last time a Democrat won a Senate race in Ohio was 1992. Brown won among voters of both genders, all age groups and all races in the state.
Sen. Bob Menendez held onto his seat in New Jersey, as did Sen. Joe Lieberman, who is projected to have narrowly averted the threat to his seat. Newcomer Ned Lamont beat Lieberman in Connecticut's Democratic primary and caused the one-time presidential candidate to run on a third-party ticket.
In Pennsylvania, projections show Sen. Rick Santorum — the third-ranking Republican in the Senate — was defeated by his pro-life Democratic opponent, State Treasurer Robert Casey Jr., the son of a popular former governor.
Among Democratic incumbents, only Menendez was considered in any real danger. But until the end, he held a 48-43 percent edge over Republican challenger Tom Kean Jr., and came out on top, according to projections.
In Tennessee's tight race to replace Bill Frist, some of the campaign tactics outshined the candidates. An ad produced by the Republican National Committee made national headlines for its steamy — and allegedly racist — content. In the ad, a young white actress talks about meeting Harold Ford, a 36-year-old who sought to become the first black southerner elected to the Senate in more than a century. At the end of the ad, she winks and says to the camera, "Harold, call me." Both candidates denounced the ad as tacky, but it became the poster child for an especially dirty campaign season.
Meanwhile, Democratic Sen. Robert Byrd retained his seat in West Virginia, and the first returns of the night made Rep. Bernie Sanders, an independent, a projected winner in the Vermont Senate race, succeeding retiring Sen. James Jeffords. Brooklyn-born with an accent to match, Sanders is an avowed Socialist who will side with Democrats when he is sworn into office in January.
Mike McCurry, former press secretary of Bill Clinton's administration, told CBS News that the apparent congressional seat gains for Democrats show that "the country is very clearly saying, 'We want a new direction.'"
Democrats appealed to voter weariness with the war, GOP White House and recent corruption scandals asto fill 33 of the Senate's 100 seats. Democrats need a net pickup of six seats to recapture the majority that they last briefly exercised in 2001-2002.
"Iraq and the economy are the main factors in this election," CBS News political consultant Harrison Hickman said. "In Ohio, the economy has a bigger impact than Iraq."
Meanwhile, Republicans' reign over theTuesday as a surge of Democratic support sparked by voter outrage over the Iraq war and disapproval of President Bush and Congress gave Democrats a chance to regain a majority in the House for the first time since 1994.
Democrats last controlled the Senate in 2002. Republicans now control 55 seats in the 100-member chamber. Two independents, Sanders and Lieberman, will caucus with the Democrats and count toward Democratic tallies. If there's a 50-50 split in the Senate, Vice President Dick Cheney serves as the tiebreaker, meaning the majority leader and committee chairs would be Republican and any split-down-the-middle votes would be decided by Cheney.
Other projected Senate wins include:
By Christine Lagorio