House races are more volatile than Senate races, but the bird's eye view for 2010 shows Democrats losing a number of seats-the question is how many. Democratic voter turnout will be lower after high turnout for President Obama's election, and swing voters have expressed dissatisfaction with congressional Democrats. Most political minds assume Speaker Nancy Pelosi's party will hold the majority, though a few have said another Republican takeover like that of 1994 is possible, especially if unemployment remains high. Democrats hold an 81-seat majority in the 435-member House, so if they lose 41 of those seats to Republicans, they lose the majority. But Republicans have their own intra-party feuds to handle. Here are seven races to watch out of 435, each of which marks trends in next year's elections.

The third-party element

NY-23, incumbent: Bill Owens (D): The GOP is on the lookout for third-party candidates that could wreck its victory parties. In the high-drama conservative vote-splitting of the NY-23 special election in November 2009, Democrat Bill Owens won a conservative district, but Republicans have high hopes to take back the seat in 2010. The GOP is less blasé about third-party candidates since Conservative Party candidate Doug Hoffman won enough backing to pressure Dede Scozzafava, a GOP moderate, out of the race, though she still siphoned off enough votes to hand victory to Owens. "Scozzafava'd" is a new political term that election created, meaning when a party turns on its own candidate. The GOP will pick its candidate much more carefully in 2010, and Hoffman, who lost by 3,000 votes, has hinted that he may run again.

The threat to veterans

MO-4, incumbent: Ike Skelton (D): Some veteran conservative Democrats who have backed Speaker Pelosi on various issues are unexpectedly vulnerable this election season. The popular disapproval of Congress and backlash against seemingly "out of touch" Washingtonians makes this election difficult for most incumbents. Sixteen-term congressman Ike Skelton, D-Mo., for one, may face a difficult reelection. While he is well-liked by both Republicans and Democrats, he voted for the stimulus package and also for the climate change bill. As chairman of the Armed Services Committee, he put forward a defense spending bill with controversial hate crimes legislation attached. Missouri Senator Claire McCaskill said Skelton is too much of an "icon" to be vulnerable, but Sen. John McCain won Skelton's district with 60 percent of the vote, and the congressman has two formidable Republican opponents already.

Rematches

MD-1, incumbent: Frank Kratovil (D): Some freshman Blue Dog Democrats may face their same challengers from 2008 in the 2010 elections, and they don't have the wind at their backs as they did then. Rep. Frank Kratovil, D-Md., will again face Republican Andy Harris, whom Kratovil defeated in 2008 only after absentee ballots were counted. Harris, a state senator, is a former physician and served in the Navy Reserves for 17 years. Kratovil has raised more money than Harris so far. After two years in the House, Kratovil has a moderate record. He bucked Democrats on key legislation like the healthcare bill and the hate crimes bill.

The underdog

LA-2, incumbent: Joseph Cao (R): Since Rep. Ahn Joseph Cao, R-La., became the first Vietnamese-American elected to Congress and the first Republican to win his district in a century, prognosticators, pundits, reporters-everybody-has predicted that he wouldn't survive another election. The numbers for Cao aren't good: His district, which is majority African-American and includes New Orleans, voted 75 percent for President Obama. Cao won partly because the election was rescheduled after a hurricane and turnout was exceptionally low. Cao hasn't voted consistently with either party: He voted against the stimulus but was the lone Republican to support the healthcare bill, and in the process he may have opened up some federal dollars for Hurricane Katrina recovery. Cao shouldn't be underestimated: No one ever thought he would win once, and so far he has good fundraising numbers for his 2010 campaign.

GOP eyes New England

CT-4, incumbent: Jim Himes (D): When Democrat Jim Himes defeated veteran Republican Chris Shays in 2008, it was the first time a Democrat had won that seat since 1969. The win colored the map of New England entirely blue, the first time that region had been exclusively Democratic in almost 150 years. Republi­can National Committee Chairman Michael Steele would dearly like to put Republicans back on that map, and Himes is a big target. Himes won by a 4 percent margin, boosted mainly by high urban turnout for President Obama, which he can't count on again. The district itself votes for fiscal conservatives and social moderates, and a few in that genre of Republicans have stepped forward to challenge Himes.

Rust Belt

PA-6, incumbent: Jim Gerlach (R): Post-industrial districts composing the Rust Belt haven't fallen into the column of one party or another, so expect tight races in that region. Pennsylvania Republican Jim Gerlach fended off Democratic contenders in close races in 2004 and 2006, one of the few Rust Belters to survive the Democratic sweep. Gerlach is running for governor of Pennsylvania now, and four Republicans are vying to replace him, with businessman Steven Welch considered the front-runner due to his personal wealth. But the Democrats have two strong challengers: Doug Pike, a former editorial writer for the Philadelphia Inquirer, and Manan Trivedi, an Iraq War veteran.

Blue Dog retirement

TN-6, Bart Gordon (D): Three Blue Dog Democrats have announced their retirement to this point, leaving their conservative districts ripe for Republican plucking. Rep. Bart Gordon (D-Tenn.) is perhaps the most striking among them, as a congressman who has held his seat for a quarter century but watched support melt away more recently. His district voted for John McCain in the 2008 election, so another Democrat less known than Gordon will have a tough job winning support. Voters seem impatient with Blue Dogs, who on the whole have generally voted with their party and not as the fiscal conservatives they promised to be. Gordon voted for the stimulus package, the borrowing-heavy 2010 budget, and the cap-and-trade bill.