2006 was a momentous year in gubernatorial races. Democrats picked up 5 open Republican-held seats (NY, MA, OH, AR, CO) and also knocked off one GOP incumbent (MD), while holding all of their seats fairly comfortably. And while some states elect their governors the same years as presidential elections, most go for the off-years for reasons I do not know.
There will be 36 states that will pick their governors two years from now and it doesn't hurt to get an early look at them (some candidates are already gearing up to run).
First of all, the two states that actually elect their governors in 2009: New Jersey and Virginia. In the former, I imagine Gov. Corzine (unpopular he may be) will poll very close with whatever Republican they put up against him, only for the final margin to not be close at all. Such is New Jersey. Virginia will be more difficult, as the state only allows Gov. Kaine a single term. The Democratic primary will likely be crowded, but the state has taken a pretty blue turn recently that should benefit whoever comes out on top.
On to 2010, 15 of the 36 seats will be open due to term limits, and that does not include incumbents who may decide to gracefully retire (such as Gibbons of Nevada and Blago of Illinois). This exodus of governors provides us with some juicy targets in blue states, but unfortunately also leaves us grasping for replacements in some solidly Republican states.
Republican Seats
ALABAMA: Gov. Riley term-limited. I like our chances here, we have a solid bench, a popular Dem Lt. Gov., and many others who could make this competitive.
ALASKA: Gov. Palin defending. Mooseburgers should easily dispatch whoever they put up against her.
CALIFORNIA: Gov. Schwarzenegger term-limited. If Tom McClintock loses in CA-04, expect him to run again for governor. Either way, Democrats have no one to blame but themselves if they fail to get the office back.
CONNECTICUT: Gov. Rell defending (maybe). She actually isn't term-limited, so if she runs again, she probably wins. If not, one of the recently defeated GOP representatives might make a go at it, but the Dem bench is better.
FLORIDA: Gov. Crist defending. Absent major scandal, he seems safe. Ambitious Dems will probably target Sen. Martinez's seat instead.
GEORGIA: Gov. Perdue term-limited. We've got a solid bench, and the state has proven more receptive to Democrats recently. The GOP probably still has the edge though.
HAWAII: Gov. Lingle term-limited. Her Lt. Gov. will attempt to keep this seat red, but Democrats are going to throw everything they've got at him. A tossup in the making.
IDAHO: Gov. Otter defending. Safe.
MINNESOTA: Gov. Pawlenty defending (maybe). Democrats ought to nab this one if it's open, if not, Pawlenty was vulnerable in 2006 so should be again.
NEBRASKA: Gov. Heinemann defending. Safe.
NEVADA: Gov. Gibbons defending (maybe). He's toast. And Democrats have surged in the state recently.
RHODE ISLAND: Gov. Carcieri term-limited. The state's blueness almost did him in in 2006, the Lt. Gov. is a Dem, and Chafee has left the GOP. There is no hope for Republicans here.
SOUTH CAROLINA: Gov. Sanford term-limited. Democrats seem resurgent here, but the statewide bench is thin at the moment.
SOUTH DAKOTA: Gov. Rounds term-limited. We'll see if the presidential purple-ness extends to the governor race.
TEXAS: Gov. Perry defending. Sen. Hutchison seems interested, if so we may not even make it competitive. Still tough to win statewide for Dems, but Texas is changing.
VERMONT: Gov. Douglas defending. He has won four straight elections now (VT and NH have two-year terms), will he go for five? He's still young, and with the strength of the third-party Progressive candidates here, Democrats don't have a chance of knocking him off.
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Democrats
ARIZONA: Gov. Napolitano retiring. We've started to build up a solid bench, but Republicans still have an edge here. AG Terry Goddard (D) is frequently mentioned as a potential successor.
ARKANSAS: Gov. Beebe defending. Despite Obama's 20 point loss, this remains a solid blue state locally. Very safe.
COLORADO: Gov. Ritter defending. The way things have gone the past four years, he's entirely safe.
ILLINOIS: Gov. Blagojevich defending (maybe). There are a few rumored primary challengers (and he would probably lose to them), but it doesn't seem likely that Republicans can win statewide anymore.
IOWA: Gov. Culver defending. Safe.
KANSAS: Gov. Sebelius term-limited. I'd like to see us hold this one, but her Lt. Gov. has his work cut out for him.
MAINE: Gov. Baldacci term-limted. Democrats have the better bench, absent one of the Senators bizarrely switching careers.
MARYLAND: Gov. O'Malley defending. Safe.
MASSACHUSETTS: Gov. Patrick defending. Odd to remember that Republicans held this office from 1990-2006. They have since become non-existent. Safe.
MICHIGAN: Gov. Granholm term-limited. The state has veered away from its temporary purple status, however the economic distress could make it a volatile race to succeed her.
NEW HAMPSHIRE: Gov. Lynch defending (maybe). Should rack up another 50 point victory if he runs, but New Hampshire has never had a four-term governor since the 1700s. He may retire or challenge Sen. Gregg, in which case there are other Democrats that may step up here.
NEW MEXICO: Gov. Richardson term-limited. Lt. Gov. Diane Denish will trounce whichever loser the GOP puts up.
NEW YORK: Gov. Paterson defending. Republicans are no longer viable statewide (they're hardly viable in red NY districts). Safe.
OHIO: Gov. Strickland defending. Moderate profile should help him rack up a massive landslide.
OKLAHOMA: Gov. Henry term-limited. We have some hope with the Lt. Gov., but this has been a brutal state to us recently.
OREGON: Gov. Kulongoski term-limited. Solid bench on our side. Will they pick the right one to beat Gordon Smith if he jumps in for a last hurrah?
PENNSYLVANIA: Gov. Rendell term-limited. Rapidly dwindling GOP bench, expanding Dem bench. I feel good about this one. We need it to undo the gerrymandering in 2012.
TENNESSEE: Gov. Bredeson term-limited. This is going to be hard. I doubt any of our Congressmen will leave their safe seats for this. However Rep. Lincoln Davis has announced he will do just that. Former Rep. Harold Ford might also make a go at it (hopefully not).
WISCONSIN: Gov. Doyle defending. He may retire after two terms, or run again. A top-tier challenger couldn't beat him in 2006, he should probably win again.
WYOMING: Gov. Freudenthal term-limited. We're screwed. Not optimistic about Trauner's potential here.
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All in all, I see four seats we're probably going to lose, but five we ought to be able to pick up. Depending on candidates, another seven from each side may be competitive. At this point, it only looks like nine Democrats and four Republicans are safe.
UPDATE: Thank you all for the comments and pointing out inaccuracies. I didn't realize so many states do not have term limits. Thanks for giving me a heads up to potential candidates as well.