I'd be a bit careful on such predictions, at this time. The problem is that now the dems, along with the media will do everything they can to blame the mess (caused by the dems) on the Republican congress. They will use this reasoning to try to get the public to blame the GOP. Indeed, they will continue to PURPOSELY destroy certain things JUST for the EXPLICIT PURPOSE of blaming the GOP.
On the same token, ANY positive attributes of legislation that the tea partiers will create will be appropriated by Obama. Just like Jerry Brown sounded like he was running like Ronald Reagan instead of, well, Jerry Brown, Obama will use the successes that the GOP brings and state that it was his and the Dems who did it. So now we have a double whammy to watch for.
The KEY...and it's a HUGE key... is for the constituents to CONSTANTLY COMMUNICATE with their constituency. They must not just legislate, but they must also EDUCATE their consituency on the actual problems and issues that are being faced. They have to realize that everyone BUT the conservatives will be doing EVERYTHING POSSIBLE to derail the GOP members in congress. For instance, they may stall a budget, then blame the GOP for stalling the budget.
What heartens me is that we have a strong undercurrent of conservatively principled members of Congress. Keep in mind that being elected is not a MANDATE. Essentially, you just passed the job interview and got hired. The TRICK is to perform so that you will be rehired. One of the advantages of winning as a conservative is that the votes that got you the victory are less malleable, as long as you stay true to conservative principle. Finally, the conservatives MUST be the ones to run the show from our side.
I'm sorry, it seemed I got a bit off track from the original premise of the thread. But it actually ties back in. Here is the list of candidates for the Senate:
Democratic incumbent elections (21)
Dianne Feinstein: California
Tom Carper: Delaware
Bill Nelson: Florida
Daniel Akaka: Hawaii
Ben Cardin: Maryland
Debbie Stabenow: Michigan
Amy Klobuchar: Minnesota
Claire McCaskill: Missouri
Jon Tester: Montana
Bob Menendez: New Jersey
Jeff Bingaman: New Mexico
Kirsten Gillibrand: New York
Kent Conrad: North Dakota
Sherrod Brown: Ohio
Bob Casey, Jr.: Pennsylvania
Sheldon Whitehouse: Rhode Island
Jim Webb: Virginia
Maria Cantwell: Washington
Joe Manchin: West Virginia
Herb Kohl: Wisconsin
Independent incumbent elections (2)
Joe Lieberman: Connecticut
Bernie Sanders: Vermont
Republican incumbent elections (10)
Jon Kyl: Arizona
Richard Lugar: Indiana
Olympia Snowe: Maine
Scott Brown: Massachusetts
Roger Wicker: Mississippi
John Ensign: Nevada
Bob Corker: Tennessee
Kay Bailey Hutchison: Texas
Orrin Hatch: Utah
John Barrasso: Wyoming
(Note: the 2010 election actually had nearly the opposite scenario; that is, far more (R) seats than (D) to defend. In short, this time around winning more than 35% of the seats is the break-even point, as opposed to the 64% last time around, which we still exceeded by 4 or more seats)