With Republican Rep. Dennis Rehberg's announcement that he will run for Senate in Montana, Republicans have a lot of momentum going into the 2012 congressional elections.
On the House side, it's hard even to guess, not knowing which Congressional Districts will exist at this time next year. Republicans are hoping that redistricting can solidify their 2010 gains enough that even a moderately bad year will not cost them their majority. In the case of a good year, the possibility of further House gains does exist, but barring an Obama implosion, Republicans are probably nearing their maximum House capacity.
In the Senate, it's the Democrats who have reached capacity -- at least in this year's Senate class. The GOP was smitten so badly in 2000 and 2006 that they just don't have that many seats to lose out of this year's Senate class. And Democrats are overextended, holding a number of seats that Republicans had or can win under the right local and national circumstances.
The Democrats' Senate boat has three large leaks already that Republicans must exploit if they hope to win a majority. If they can't win in these states, they're probably in for a big disappointment next fall:
Montana: People just assume that Montana is a reliably Republican state. It isn't. President Obama got 47.1 percent there in 2008. And the state's Democrats have had such a strong showing in the last decade that there is only one Republican officeholder prominent enough to begin on equal footing with tobacco-chewing incumbent, Sen. Jon Tester, D.
Luckily for the GOP, that official, Rehberg, threw his hat in the ring over the weekend. Tester narrowly won his seat in 2006 after hammering former Sen. Conrad Burns, R, over political donations he had received from disgraced former lobbyist Jack Abramoff. (Burns did himself no favors in that race, either.) Montana is still conservative enough, and Rehberg sufficiently well known, to make this a great opportunity. But the state's Republicans haven't won a close top-ticket race in Montana in years.
Nebraska: Sen. Ben Nelson, D, a former governor, was far too popular to be beaten in 2006, but now he's become the butt of national jokes after selling his vote to the Obama administration on both the stimulus package and the health care bill. He trails two likely GOP opponents, including the man he defeated in 2000.
North Dakota: The retirement of Sen. Kent Conrad, D-N.D., leaves a huge hole for Democrats. North Dakota really is a reliably Republican state, and it's probably the most ripe for a GOP pickup so far.