The Hotline's House Race Rankings

At this point last year, Pres. Obama had just been sworn in after winning a rather comfortable victory, and the House and Senate (with their expanded Democratic majorities) were preparing to push through his agenda. The public was just as enamored with congressional Dems as they were on Election Day; voters gave them a 46 percent to 22 percent lead over Republicans on the generic congressional ballot.

But things have certainly changed in the span of that year. Obama's approval ratings are now hovering down around 50 percent, and Republicans are tied with Dems on the generic ballot. So, while Republican Scott Brown's victory in the Massachusetts Senate race on Tuesday may have been shocking, it was no accident. Democrats are in trouble, and they will spend most of their resources and time this year defending the seats they already have.

You'll see that reflected below in The Hotline's first House race rankings of 2010.

The top 5 seats most likely to change hands next year:

1. LA-02: Rep. Anh "Joseph" Cao (R) -- state Rep. Cedric Richmond (D) faces a contested primary, but Democrats inside and outside the district (former Sen. John Breaux and several of his '08 opponents) appear to be coalescing behind his candidacy. That's bad news for Cao, who needs a flawed Democrat to emerge from a very bloody primary if he's to have any shot at winning. Without those ingredients, the fundamentals of this 75-percent Obama district will be just too difficult for him to overcome.

2. DE-AL: Open seat held by Rep. Mike Castle (R) -- It's been three months since Castle's Senate announcement, and no high-profile Republicans have stepped up to run. Meanwhile, ex-LG John Carney (D) has used the time to build a substantial war chest. If the GOP has any hope of holding this seat, they'll need to find a top-tier challenger fast. It doesn't look like it's going to happen.

3. TN-06: Open seat held by Rep. Bart Gordon (D) -- Republicans planned to target Rep. Gordon anyway, but his retirement has opened a scramble on the GOP side. Several challengers, including state Sens. Jim Tracy and Diane Black, as well as activist Lou Ann Zelenik, have all descended on the race, and so have a few businessmen. Conversely, no Democrat has yet decided to run here. With the district's GOP lean (it gave John McCain 62 percent, after awarding Pres. Bush 60 percent four years earlier), it's almost impossible to see how Dems can convince a top-tier challenger to run -- and that'll be needed to put this seat in play.

4. LA-03: Open seat held by Rep. Charlie Melancon (D) -- We're less than 10 months away from Election Day, and the fields are far from set in this contest. But that's normal in LA, where primary day is in August. Attorney Ravi Sangisetty is running on the Dem side, and by the end of the year had a respectable $225K on hand. On the GOP side, state Rep. Nickie Monica recently announced his long-expected bid. But the candidate both sides are waiting on is state DNR Sec. Scott Angelle, who is determining whether to run, and if he does, whether to run as a GOPer or Dem.

5. KS-03: Open seat held by Rep. Dennis Moore (D) -- Moore announced his retirement in late November, and months later, we're still waiting for a Democratic candidate to emerge. Several strong Republicans, including '08 nominee Nick Jordan and state Rep. Kevin Yoder, jumped at the chance to run in the open seat. This is not unfriendly territory for Dems: Pres. Obama took advantage of black turnout in Kansas City, as well as support in KU-dominated Douglas Co., to win 51 percent here in '08. Kansas City, Kan. Mayor Joe Reardon (D) is considering a bid, but is he the best candidate? The key to Moore's longevity was that he could be competitive in the suburbs (his home base), while racking up large margins in the city. A suburban candidate would be ideal, but Dems can't afford to be picky at this point.

Check out The Hotline's top 25 House races at NationalJournal.com.