WASHINGTON -- Democrats were poised Tuesday to retain a narrow majority in the Senate, but Republicans are keeping their grip on the House, delivering what it is expected to be another divided, and highly polarized, Congress.
Neither record-low job approval ratings nor an avalanche of campaign spending appeared able to shake the dynamic that made the last Congress the most partisan since the Civil War. The few remaining moderate lawmakers were endangered.
"That's the sort of sad state of affairs: You're not going to have much change in Congress," said Keith Poole, a political science professor at the University of Georgia, who has researched decades of congressional voting patterns. "That's a real recipe for confrontation after the election."
Republicans had high hopes of wresting control of the Senate from Democrats, as President Barack Obama's popularity slid and Democratic incumbents faced a less favorable political climate than six years ago when many first-term senators won in a wave that gave their party the majority.
Democrats had nearly two dozen seats to defend, twice as many as Republicans, who needed four seats to tip the 53-47 balance _ or three if Mitt Romney became the Republican president and Rep. Paul D. Ryan the tie-breaking vote in the Senate.
But the decision by Republican leaders to stay out of the primary process shifted the landscape. Tea party-styled Republicans were nominated in Missouri and Indiana, making those states more competitive.
At the same time, Democratic candidates appeared to be holding their own in key swing states. In Ohio, one of the most liberal Democrats, Sen. Sherrod Brown, remained popular after his first term, and in Florida, Democratic Sen. Bill Nelson was easily re-elected, according to The Associated Press.
However Montana's Democratic Sen. Jon Tester faced a difficult challenge from Republican Rep. Denny Rehberg, and in Wisconsin, the open seat held by a retiring Democrat was rated a toss-up.
One critical battleground, Virginia, was a battle between two political giants, Tim Kaine and George Allen, former governors locked in a dead heat. Allen, the towering son of the former football coach, sought to retake the Senate seat he lost six years ago after uttering a racial slur, but Kaine made an appeal to women, minorities and independents put off by Allen's conservative tilt.
Republicans had some marquee seats to defend, including in Massachusetts. Sen. Scott Brown helped launch the 2010 tea party wave by winning the seat that came open after Sen. Edward Kennedy died. He was locked in a tight race with Elizabeth Warren, the liberal Harvard professor who had been Obama's choice to run the new consumer financial protection bureau.
With the once-broad playing field narrowed, the chance for a wholesale makeover in the Senate, and with it a mandate for governing, seemed to slip away from the Republicans.
Conservative Republican Senate candidates Todd Akin in Missouri and Richard Mourdock in Indiana spun their races into turmoil after making anti-abortion comments seen as too severe. Akin suggested that pregnancy rarely results from "legitimate rape," while Mourdock said that even pregnancy from rape was a life had God "intended."
Missouri's Democratic Sen. Claire McCaskill had once been a prime GOP target as an ally of Obama, but Akin's comments narrowed the race. Indiana, another state that soured on Obama, became competitive for Democratic Rep. Joe Donnelly.
One key Republican-held seat was in Nevada, where Sen. Dean Heller, who was appointed to office after his Republican predecessor resigned amid a sex and lobby scandal, was challenged by Democratic Rep. Shelley Berkley, the congresswoman from Las Vegas.
The Republican strongholds of Nebraska and North Dakota had been considered easy flips to the GOP column with the retirement of Democratic senators. But Democrat Heidi Heitkamp, the former North Dakota attorney general, proved to be a robust campaigner against Republican Rep. Rick Berg.
Republicans had a better chance in Nebraska, where former Democratic Sen. Bob Kerrey, once the state's governor, was struggling to make a comeback against Republican Deb Fischer, a Sarah Palin-backed state legislator.
A record number of women ran for the Senate, which could see its first openly lesbian senator if Democrat Tammy Baldwin, the congresswoman from Madison, prevails over former Gov. Tommy Thompson in Wisconsin. Hawaii's Democratic Rep. Mazie Hirono would become the first Asian-American woman in the Senate if she defeats Republican former Gov. Linda Lingle.
Perhaps one race brought the most uncertainty: In Maine, the independent former governor, Angus King, declined to say which party he would caucus with, although he is expected to join Democrats.On Tuesday, according to The Associated Press, he claimed the seat held by retiring Republican Sen. Olympia Snowe, one of the few moderates in Congress.