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First Read's Top 10 Senate takeovers

From The NBC Political Unit
With the news that DNC Chairman and former Virginia Gov. Tim Kaine (D) is “increasingly likely” to run in Virginia and Rep. Dean Heller (R) getting into the Nevada race, we thought we’d bring you another Senate Top 10, our second of the year. (Numbers in parentheses represent its previous ranking.)

Republicans need to flip three seats to take control of the Senate. Eight of our Top 10 are Democratic-held seats.

1. North Dakota (D) (1): Still No. 1 and probably be there for a while with Sen. Kent Conrad’s (D) decision to retire.

2. Nebraska (D) (3): Sen. Ben Nelson (D) is the most vulnerable incumbent in the country and is going to get a strong GOP challenger. Nelson was ranked the most conservative Democrat in the Senate in 2010, but Republicans hope the bad press Nelson received for the “Cornhusker Kickback” during the health-care debate will be the boost they need. The GOP challengers: Jon Bruning (state attorney general) and Don Stenberg (state treasurer). By the way, this would be Stenberg’s fourth (!) run at the Senate seat. Nelson is happy about Stenberg's entrance if only to keep the GOP primary active.

3. Montana (D) (4): Freshman Democrat Jon Tester has been highlighting spending cutbacks, but he could still face an uphill battle. He narrowly won in 2006 against a flawed candidate, and he faces a real Republican challenger in Rep. Denny Rehberg. Notice Rehberg was minding his right flank with his NO vote on the C.R.

4. Missouri (D) (6): Sen. Claire McCaskill has worked to carve out a role as a Truman-esque watchdog in the Senate, but her constituents – especially independents -- haven’t rewarded her efforts with robust approval ratings. A recent tough news story about her use of taxpayer money for private planes will be fodder for attacks. Remember, the issue for McCaskill is that most Missourians don't fly on private planes, period, no matter who pays for it.

5. Virginia (D) (5): Political junkies are smiling at the thought of a matchup between former Gov. Tim Kaine and ’06 Senate race loser George Allen (who’ll have to beat back a Tea Party primary challenge). We’ve already predicted a 51%-49% race, and we’re stickin’ to it with the presidential winner carrying the senate nominee.

6. New Mexico (D) (unranked): Jeff Bingaman’s retirement puts this seat in play, but it could be a tough get for Republicans in a state that swung for Obama in 2008. Former Rep. Heather Wilson (R) is considered the strongest GOP candidate but will likely face a thorny path through the primary to the general election.

7. Nevada (R) (2): Finally, we get to a Democratic target. Heller’s entrance gave Republicans a much better chance at holding this seat than if John Ensign stayed in the race. A Democratic candidate has yet to emerge. Do Democrats face a crowded primary or can they clear the field for a one-on-one with Heller? In a presidential year, this is going to be a hotly contested battleground with the president trying to mobilize the Hispanic base that makes up 27% of the state’s electorate.

8. Massachusetts (R) (7): This is probably potentially Democrats’ best pickup opportunity. But Scott Brown (R) remains the most popular politician in the state. As the campaign heats up and a Democratic opponent emerges does some of that start to change in this reliably blue state?

9. Florida (D) (8): Like Nevada and Ohio, there is going to be a lot of activity in this state in a presidential year. Can Bill Nelson hang on in the state that elected Rick Scott (R) governor in 2010?

10. Michigan (D) (9): Is Obama’s campaigning in the state going to be enough to put Sen. Debbie Stabenow (D) over the finish line? A poll out at the end of February showed her only beating Rep. Pete Hoekstra (R) by two percentage points.

Other Senate races on our radar (in alphabetical order): AZ, CT, IN (does Lugar survive a primary), ME (ditto for Olympia Snowe), NJ (Menendez’s race in ’06 was very tight), OH (Sen. Sherrod Brown’s (D) poll numbers look good right now. But a lot can change in this key presidential state), PA, TX (Dems always think they can play here because of the demographic changes, but the bench is really thin), WA, WI (does Herb Kohl retire?), WV.