Democrats will maintain control of the U.S. Senate after their candidates picked up Republican-held seats in Indiana, Maine and Massachusetts, leaving the GOP no path to a takeover with the remaining competitive races that remain undecided.
Senate Majority Leader Harry Reid, D-Nev., offered a concillatory tone and called for compromise as Congress faces a daunting series of fiscal challenges in the months ahead.
"Democrats and Republicans must come together, and show that we are up to the challenge," Reid said. "This is no time for excuses. This is no time for putting things off until later. We can achieve big things when we work together."
It is the second election cycle in a row in which Republicans were favored to make gains because they were defending fewer seats, only to see their chances diminish because of missteps by their own candidates.
Sen. John Cornyn, R-Texas, chairman of the National Republican Senatorial Committee, said the party needs to take some time to process the impact of Tuesday's results.
"It's clear that with our losses in the Presidential race, and a number of key Senate races, we have a period of reflection and recalibration ahead for the Republican Party," Cornyn said. "While some will want to blame one wing of the party over the other, the reality is candidates from all corners of our GOP lost tonight. Clearly we have work to do in the weeks and months ahead."
STORY: GOP keeps control of House
In Indiana, Republican Richard Mourdock failed to recover from a late controversy over his remarks at a debate that pregnancy resulting from rape is "God's will" in explaining his opposition to abortion rights. Democratic Rep. Joe Donnelly was declared the winner by a narrow margin in a victory that delivered a fatal blow to lingering GOP hopes for a takeover.
Harvard University professor and former Obama administration official Elizabeth Warren handily defeated GOP Sen. Scott Brown in one of the highest-profile races of the 2012 cycle, and the most costly in the state's history. Her victory was critical to Democrats' efforts to maintain control and hailed by liberal activists who supported her campaign.
In Maine, former Gov. Angus King sailed to victory despite the GOP's best efforts to make it a competitive race. King ran as an independent and has not said which party he intends to caucus with, but he is widely expected to sit with Democrats in the chamber. To that end, King criticized GOP strategist Karl Rove in his victory speech for directing super PAC money into Maine in an effort to defeat King. "I hope that man never comes to Maine," King said.
An early duo of Democratic re-election victories came in Ohio for Sen. Sherrod Brown and in Florida for Sen. BIll Nelson, thwarting long-shot GOP efforts for pick-ups in those states. Recent Democratic concerns about Connecticut quickly evaporated after Democratic Rep. Chris Murphy handily defeated former World Wrestling Entertainment CEO Linda McMahon, who spent nearly $100 million of her own fortune for a Senate seat in 2010 and 2012.
In Missouri, Democratic Sen. Claire McCaskill, who was targeted heavily by Republicans, pulled out a convincing win against Republican Rep. Todd Akin, whose campaign foundered after he claimed that women who were victims of rape had a biological defense against becoming pregnant.
Former Democratic Gov. Tim Kaine defeated Republican former governor and senator George Allen in the hotly contested Virginia race, maintaining the party's hold on the seat. Democratic Rep. Tammy Baldwin defeated former GOP Gov. Tommy Thompson in Wisconsin and made history: She is the first openly gay person elected to the U.S. Senate.
Republicans scored a rare victory in Nebraska, where Republican Deb Fischer defeated former Democratic Sen. Bob Kerrey, who was seeking a comeback. Fischer's victory was a GOP pick-up because the seat is currently held by retiring Democratic Sen. Ben Nelson. GOP Rep. Jeff Flake also handily won in Arizona against Democrat Richard Carmona. Texas also elected Republican Ted Cruz, a popular candidate among Tea Party activists.
In Nevada, Democratic Rep. Shelley Berkley held a narrow lead over GOP Sen. Dean Heller, another potential Democratic pick-up, but the race remained tight. Republicans were also eyeing a potential pick-up in North Dakota, where Democrat Heidi Heitkamp held a narrow lead over GOP Rep. Rick Berg in a state Republican Mitt Romney won easily.
If either Berkley or Heitkamp secures a victory, 2012 would make history for sending a new record of non-incumbent freshman women senators to the Senate. The record was set in 1996 when four new women were sent to the Senate. Four women have already won including Baldwin, Fischer, Warren and Democrat Mazie Hirono in Hawaii.
Montana was too close to call in a race pitting incumbent Democratic Sen. Jon Tester against GOP Rep. Denny Rehberg in a state Romney carried comfortably.
There were 33 Senate seats up for re-election, 23 Democrats and 10 Republicans, and most incumbents were favored to win handily. Five Republican senators and 17 Democratic senators faced no real re-election threat. With Republicans maintaining control of the U.S. House, Congress will be divided by near-identical margins next year.
By Susan Davis