Not to pile on about the tanking of Arnold (see R. Michael Alvarez post below) and other GOP Govs, but My DD‘s Chris Bowers paints a very bright picture of Democratic prospects for taking the GOP-held governorships of several of the most populous States. Do visit his website and read “The Big Democratic Opportunity of 2006: Governors.” Here’s some teasers:

Ohio. Bob Taft has the lowest approval rating of any Governor in the nation. Mike DeWine has the lowest approval rating of any Senator up for re-election in 2006. Republicans in the state are embroiled in Coin-gate, and congressman Bob Ney is even deeper in Abramoff’s pocket than DeLay. Democrats can easily gain on every level here in 2006.
California. In the largest state in the Union, Schwarzenegger is circling the drain…
New York. Right now, there does not seem to be any realistic scenario under which Spitzer will not win this race in 2006. Already, he regularly leads Pataki with more than 50% of the vote, while Pataki rots in the thirties. Incumbents can’t pull out of tailspins like that….
Massachusetts. Multiple polls…have shown that Romney is in a lot of trouble in the most Democratic state in the nation.

Bowers discusses the Dems improving prospects in seven states in all, and savors the implications:

All seven of these states are ripe. Here is how sweet a sweep of these seven would be:
Right now, these are the seven largest states with Republican Governors, and combine for over 40% of the national population. Victory across the board would push Democrats in control of states worth around 400 electoral votes, rendering Republicans a small minority party when it comes to Governors.
Republican gerrymanders in Georgia, Ohio, Florida and Texas would be threatened, if not entirely done away with, come 2010. Control of elections in uber-swing states Florida and Ohio would no longer be in Republican hands.
The weakness of Republican Governors in large states presents Democrats with an opportunity to thoroughly reshape the American political landscape. We have waited some time for the Emerging Democratic majority to emerge, and these seven states represent our best chance to make it happen. This is our prize. This is our chance. We have to make it happen.