In the middle-class Cleveland suburb of Parma Heights, Ohio, Fred Peck, 48, explained his vote for Republicans -- and by extension against President Barack Obama's agenda -- by pointing to a 20 percent increase in his health care premiums and the declining value of his retirement fund. "I see nothing changing for the better," said Peck, who works in university campus maintenance.
In Miami's liberal Coconut Grove neighborhood, teacher Steve Wise, 28, voted for independent Charlie Crist for the Senate and Democrats for other offices. Mostly, he welcomed the end of a national campaign so often toxic in its tone. "I just want this day to be over," he said. "Because it's been too much -- political ads, newscasts, too much talking heads. I just want to move on and get this country back."
In Pelham, N.Y., Raymond Garofano, 66, who works in packaging for Revlon, voted a straight Democratic ticket and allowed that Obama "is doing an adequate job. Nobody's perfect."
Republicans buoyantly forecast that they would win the House and usher in a new era of shared governance, two years after Democrats sealed victory in the presidency, the House and the Senate and set about reshaping the agenda in a time of severe recession and war. Democrats did not seriously dispute expectations that they would lose the House this time, even while campaigning through the final hours to stem losses.
"This is going to be a big day," House Republican Leader John Boehner, likely to become speaker if the GOP wins the House, said after voting at a church near his West Chester, Ohio, suburban home. He said that for those who think the government is spending too much and bailing out too many, "this is their opportunity to be heard."
Democrats tend to be strong closers, with a vaunted operation by the party, Obama's organizers and unions to get supporters to voting sites on Election Day. This time, they faced a ground game infused by the tea party, less polished than the other side but full of energy.
The midterm elections are a prime-time test for that loosely knit and largely leaderless coalition, a force unheard of just two years ago. Tea party supporters rattled the Republican establishment in the primaries, booting out several veteran lawmakers and installing more than 70 candidates, nearly three dozen of whom are in competitive races Tuesday.
If successful, that conservative movement could come to Washington as a firewall against expansive federal spending, immigration liberalization and more, as well as a further threat to the historic health care law that Republicans hope somehow to roll back.
Democrats have had to struggle against apathy by their supporters and many who motivated themselves to vote Tuesday sounded lukewarm about Obama even as they cast ballots for his party.
"I think he's doing OK, I wouldn't say great, I wouldn't say horrible," said Heather Walczuk, 26, a social worker in Manhattan. She moved from Virginia a few years ago and used to vote Republican but has changed. She reported that her mother recently joined the tea party. "I don't think she fully, really, knows what exactly she's involved in or everything that they stand for," she said.
At a precinct in Windsor Heights, a western suburb of Des Moines, Iowa, several voters said it might be a good thing to have Democrats and Republicans sharing power, and Obama's reach curbed.
"I voted mostly Republican," said Jodi Alberts, 47, an insurance company worker. "I think some of his policies are a little bit too social. We need to rein him in."
Kelly Travis, 46, a homemaker, said of her votes: "I kind of mixed it up. I don't like it when they talk about growing government. I guess I did want to send a signal."
Boehner promised Monday to hold weekly votes to cut federal spending, make jobs the top GOP priority and fight to repeal the health law. Former President Bill Clinton, campaigning for Democrats as if his own future were on the line, stumped late into the night in New York, Pennsylvania, West Virginia, Kentucky and Florida.
Republicans need 40 more seats to win the House, a goal that polls indicated they might achieve. Races for more than 100 of the 435 seats are competitive.
Republicans need a net gain of 10 to take the Senate, a tougher road that requires them to win every tight race. The GOP also made strong bids to add governors to their ranks and expand in state legislatures.
Voter mobilization efforts have been unfolding for weeks as more than 14 million Americans cast early ballots.
In Nevada, home of the hot Senate contest between Democratic Majority Leader Harry Reid and tea-party pick Sharron Angle, registered Democrats and Republicans came out early in similar numbers. In Pennsylvania, another battleground, more than half the early voters were Republican, by the latest count.
Some races could go days or more without a winner, thanks to the multitude of expected close contests -- in Colorado, Nevada, Illinois, West Virginia, Ohio, Alaska and more -- and the persistence of shaky voting systems in some places a decade after the presidential-election counting disaster in Florida.
Hundreds of lawyers from both sides are ready to roll. This was a campaign marked by the ragged anger of partisans and caustic ads by candidates, now spilling into an Election Day that's likely to lead to complaints of voting irregularities, fraud or machine meltdowns -- and hair-trigger legal challenges.
One of the most unpredictable races was unfolding in Alaska, where Sen. Lisa Murkowski, upset in the GOP primaries by the tea party's pick, Joe Miller, is trying to win by having voters write her name on the ballot. Democrats injected cash late in the campaign to try to lift their candidate, Scott McAdams, over the other two.
Voters in 37 states are electing governors. Among the most competitive: the contest in Ohio between Democratic Gov. Ted Strickland and former Republican Rep. John Kasich.
AP writers Rasha Madkour in Miami; Mike Glover in Des Moines, Iowa; Thomas J. Sheeran in Parma Heights, Ohio; Kristen Wyatt in Thornton, Colo.; and Michael R. Blood, Cristina Silva in Las Vegas and Deepti Hajela in New York contributed to this report.