Anh “Joseph” Cao (R-La.)1st term (50 percent)

Cao, the only Republican on the list, has made some earnest efforts to endear himself to voters in an overwhelmingly Democratic, majority-black, New Orleans-based district. But Cao won in 2008 because Democratic incumbent William Jefferson was indicted (and later convicted) on corruption charges. Cao has broken at times with his party’s leadership, and he was the only Republican to vote for the original House version of the health care overhaul. But how does he stay in office without a badly tainted opponent? State Reps. Cedric Richmond and Juan LaFonta will face off in the Aug. 28 Democratic primary.

Travis Childers (D-Miss.)2nd term (54 percent)

Few endangered Democrats are better suited to ride out whatever Republican tide is building than Childers, who won his northern Mississippi seat twice in 2008, in a May special election and in November. The longtime county official and nursing home owner is a social and fiscal conservative who has often broken with his party’s leaders on key issues, including the health care legislation. And as a devout Baptist, he has much in common with many constituents. But his heavily Republican district is tough for a Democrat. He’ll likely face state Sen. Alan Nunnelee (R), who is from Tupelo, which is a much better geographic base than the 2008 GOP nominee had.

Steve Driehaus (D-Ohio)1st term (52 percent)

Losing candidates who seek rematches historically do not win. But in a national political environment favoring a Republican comeback, Driehaus faces a serious threat from former Rep. Steve Chabot, the seven-term incumbent he unseated in 2008. Representing a Cincinnati-based swing district, he’s being hammered by Republicans for backing controversial Democratic initiatives such as the stimulus bill, the cap-and-trade energy bill and the health care overhaul. Driehaus also won’t have a huge African-American turnout to boost him this time. But he is well-funded, having outraised Chabot $1.2 million to $992,000 as of April 14, and also led in cash on hand. This will be a marquee slugfest.

Mary Jo Kilroy (D-Ohio)1st term (46 percent)

It took two tries for Kilroy to win her Columbus-area seat in much better Democratic times. She has another round with Steve Stivers, a former state Senator who in 2008 came within less than a point of keeping an open seat in GOP hands. Kilroy has voted the gamut of Obama administration priorities and is being tied by Republicans to Speaker Nancy Pelosi (D-Calif.). But Kilroy’s camp, in a replay of 2008, is highlighting Stivers’ past stint as a bank lobbyist and is tying him to former President George W. Bush. In a heavy Republican year, it may not be enough.

Frank Kratovil (D-Md.)1st term (49 percent)

It is hard to imagine Kratovil finding a way to return for the 112th Congress, considering all the signs point to this being an abysmal Democratic year. He represents a district that includes the conservative Eastern Shore and parts of suburban Baltimore, across the bay, that also lean right, and he won by less than a point. But he did buck his party leadership on a third of House votes in 2009. He is well-funded, but it may not matter in his rematch from 2008 with state Sen. Andy Harris, who is running a better campaign than he did two years ago and has a more unified GOP behind him this time.

Betsy Markey (D-Colo.)1st term (56 percent)

Markey, a businesswoman and former aide to then-Sen. Ken Salazar, made an impressive debut in 2008 when she ousted Republican incumbent Marilyn Musgrave by more than 12 points. But she did so in a sprawling Colorado district that narrowly backed Sen. John McCain (R-Ariz.) in 2008 and usually is even more favorable GOP turf. Republicans are branding her a flip-flopper, as she voted against the original House health care bill but voted for the final version. Nonetheless, Markey has prepared for a GOP onslaught, joining the Blue Dog Coalition and ending March with more than $1.2 million in cash on hand. That figure more than doubled the account of state Rep. Cory Gardner, the favorite for the Republican nomination.

Walt Minnick (D-Idaho)1st term (51 percent)

The Democratic upsurge in 2006 and 2008 carried in several Members who represent districts that usually are Republican strongholds. This year, these Members will have to convince their voters that they are not like “those” Democrats in Washington. No one has done more to make that case than Minnick, a businessman who in 2008 edged one-term GOP Rep. Bill Sali by 1 point in an overwhelmingly Republican district. Minnick broke the party line almost three-fifths of the time last year. That gives him a chance against the winner of next week’s Republican primary between Marine Corps veteran Vaughn Ward and state Rep. Raul Labrador.

Glenn Nye (D-Va.)1st term (52 percent)

Republicans think this will be a good year to send both Nye and fellow Virginia freshman Tom Perriello — who scored upsets over GOP incumbents — quickly packing. Nye, a former international development official who defeated Rep. Thelma Drake by 5 points, has generally kept a low profile and has distanced himself from the House Democratic leadership, going against the party line almost a third of the time last year and opposing the health care legislation. Auto dealer Scott Rigell is the likely GOP nominee.

Tom Perriello (D-Va.)1st term (50 percent)

Unlike Nye, who won last time by a fairly comfortable margin, Perriello unseated Rep. Virgil Goode by two-tenths of a point in a district that has an overall conservative lean. The founder of a nonprofit human rights organization, Perriello benefited from strong turnout for Barack Obama around liberal-leaning Charlottesville — home to University of Virginia — which limited McCain to a 3-point margin in what is usually a GOP presidential stronghold. Perriello is on his own this year when he’ll face the winner of a crowded, divisive primary in which state Sen. Robert Hurt is the favorite of the Republican establishment. But Perriello is an eager campaigner who again is showing a knack for raising big money.

Harry Teague (D-N.M.)1st term (56 percent)

Teague will have to squeeze as much mileage as he can from his likable working-class persona if he is to fend off the comeback attempt by his predecessor, Republican Steve Pearce. Pearce’s conservative leanings may fit the electorate’s mood, and he and his supporters have hammered Teague’s votes last year for the economic stimulus legislation and the cap-and-trade proposal — which was terribly unpopular in his energy-producing district. But Teague has broken with his party on some key issues, including health care. And Pearce may be testing the limits for a candidate trying to rebound from a disastrous statewide bid in 2008. Both Teague and Pearce are amply funded oilmen from the same part of the sprawling district.