Voters deeply worried

Exit polls found voters deeply worried about the economy, with eight in 10 saying it was a chief concern. Nearly three-quarters believed government did not function properly, and four in 10 said they supported the conservative Tea Party movement of Republicans.

"The people in the heartland, I think it is safe to say, are fearful. They are angry. And they are feeling very strongly that the folks in Washington, in both political parties, just don't seem to get it," said Jim Slattery, a former Democratic representative from Kansas.

The Republican rout extended from coast to coast and knocked more than 30 Democratic incumbents out of the House, including Armed Services Committee Chairman Ike Skelton, Budget Committee Chairman John Spratt and Transportation Committee Chairman James Oberstar.

Obama said he felt "sadness" at the loss of so many Democrats who had taken tough votes to back the healthcare overhaul, economic stimulus package and other initiatives.

"It's hard, and I take responsibility for it in a lot of ways," he said. "There is also a lot of questioning on my part in terms of, 'Could I have done something differently or done something more so that those folks would still be here?'"

Obama said there might be room for agreement with Republicans on areas like natural gas, energy issues and reducing "earmarks" -- local spending projects funded by Congress.

"If the president would like to partner in this effort, I gladly take him up on that offer," Eric Cantor, the No. 2 House Republican, said of the earmarks issue.

Investors said they expected Republicans to be more sympathetic to business concerns. The S&P ended at a six-month high, up 0.37 percent, on Wednesday after the Federal Reserve Board announced plans to aid the economy.

Boehner said the sweeping healthcare overhaul passed by Democrats in March would ruin the medical system and bankrupt the country. "That means we have to do everything we can to try to repeal this bill and replace it with common sense reforms to bring down the cost of healthcare," he said.

Obama said he did not believe the election was a repudiation of the healthcare overhaul, and he would be willing to work with Republicans on "tweaks."

Democrats, who have denounced Boehner the past two years as an obstructionist, expressed hope they can now work with him.