Overriding those changes, though, is a thinning of pragmatic, centrist veterans in both parties. Among those leaving are some of the Senate's most pragmatic lawmakers, nearly half the House's centrist Blue Dog Democrats and several moderate House Republicans.
That could leave the parties more polarized even as President Barack Obama and congressional leaders talk up the cooperation needed to tackle complex, vexing problems such as curbing deficits, revamping tax laws and culling savings from Medicare and other costly, popular programs.
"This movement away from the center, at a time when issues have to be resolved from the middle, makes it much more difficult to find solutions to major problems," said William Hoagland, senior vice president of the Bipartisan Policy Center, a private group advocating compromise.
In the Senate, moderate Scott Brown, R-Mass., lost to Democrat Elizabeth Warren, who will be one of the most liberal members. Another GOP moderate, Richard Lugar of Indiana, fell in the primary election. Two others, Kay Bailey Hutchison of Texas and Olympia Snowe of Maine, are retiring.
Moderate Democratic senators such as Kent Conrad of North Dakota, Herb Kohl of Wisconsin, Ben Nelson of Nebraska, Jim Webb of Virginia are leaving, as is Democratic-leaning independent Joe Lieberman.
While about half the incoming 12 Senate freshmen of both parties are moderates, new arrivals include tea party Republican Ted Cruz of Texas, conservative Deb Fischer of Nebraska, and liberals such as Tammy Baldwin of Wisconsin and Hawaii's Mazie Hirono.
There's a similar pattern in the House, where 10 of the 24 Democratic Blue Dogs lost, are retiring or, in the case of Rep. Joe Donnelly, D-Ind., are moving to the Senate. That will further slash a centrist group that just a few years ago had more than 50 members, though some new freshmen might join.
Among Republicans, moderates like Reps. Judy Biggert of Illinois and New Hampshire's Charles Bass were defeated while others such as Reps. Jerry Lewis of California and Steven LaTourette of Ohio decided to retire.
"Congress seems to be going in the opposite direction of the country, just as the country is screaming for solutions to gridlock," said Democratic strategist Phil Singer.
Whether the changes are good is often in the eye of the beholder.
Seventy-one of the 83 House GOP freshmen of 2010 were re-elected Nov. 6, but 11 lost, including one of the group's highest profile members, conservative Rep. Allen West, R-Fla. Another faces a runoff in December.
"Some of the people who are the anti-government ideologues, some of them are gone," said House Minority Leader Nancy Pelosi, D-Calif. "And that message has been rejected by the American people."
Sal Russo, strategist for the Tea Party Express, said such departures would be balanced by newly elected conservatives, including the Senate's Cruz and GOP Reps.-elect Ted Yoho of Florida and Mark Meadows of North Carolina.
"Pretty much everybody that ran in 2012 was talking about the economic woes we face, stopping excessive spending, controlling unsustainable debt," he said.
[to top of second column]
Overall, the new House is on track for a 234-201 Republican majority, a narrowing of their 242-193 advantage today, which includes five vacancies. Democrats will control the Senate 55-45, up from 53-47.
A dozen of the 100 senators and at least 81 of the 435 House members, almost one-fifth, will be in their first term, slightly above historic averages. The Associated Press hasn't declared winners in two House races.
Many newcomers, in Washington for orientation sessions after their election, described a need to compromise. Some also made it clear there will be plenty of fuel for partisan clashes.
"I'm going in open-minded," said conservative Rep.-elect Roger Williams, R-Texas. "But I have certain core values like we all do and I'm not going to waver on that."
All together, there will be 73 women in the House and 20 in the Senate. Both are records.
For the first time, more than half of House Democrats -- 105, in this case -- will not be white males.
One white male will be Rep.-elect Joseph Kennedy III, a Massachusetts Democrat whose father was Rep. Joe Kennedy, D-Mass., and grandfather was New York Sen. and Democratic presidential candidate Robert Kennedy. When the newest Kennedy takes office, it will end the only two years since 1947 without a member of his family in Congress.
Those leaving include several who have been in the middle of recent years' policy battles.
Among them are Sen. Jon Kyl, R-Ariz., the GOP's No. 2 Senate leader; Indiana's Lugar, a longtime GOP power on foreign policy; North Dakota's Conrad, the Senate Budget Committee chairman and one of his party's chief deficit foes; and Jeff Bingaman, D-N.M., who heads the Senate Energy and Natural Resources Committee.
Gone from the House will be California Democratic Reps. Pete Stark, a major force on health issues, and Howard Berman, long influential in foreign affairs, plus liberal Massachusetts stalwart Barney Frank, whose name is on the new law overhauling the government's regulation of banks and other financial institutions.
Also leaving: House Rules Committee Chairman David Dreier, R-Calif., and Ron Paul, 77, who charted his own libertarian course in Congress and long-shot campaigns for the GOP presidential nomination in 2008 and 2012.
"The status quo will continue," Paul, who sees little difference between the two political parties, said of the new Congress. As for his own departure, he said, "Nobody will notice."
Press; By ALAN FRAM]
Copyright 2012 The Associated
Press. All rights reserved. This material may not be published,
broadcast, rewritten or redistributed.