What a day for Democrats. First, Lt. Gov. John Cherry (D) announced he was dropping out of the Michigan gubernatorial race. Then Sen. Byron Dorgan (D) stunned Washington by announcing he would not seek re-election. And tonight, word from Colorado that Gov. Bill Ritter (D) will not seek re-election.

Ritter won in a landslide in 2006, but has had a rocky tenure since then. He was considered one of the weakest incumbent governors in the country, and so his departure could actually clear the way for a stronger candidate free of the "status quo" label in what is shaping up to be an anti-incumbent year.

Democrats would be eager to see former state House Speaker Andrew Romanoff switch to the governor race instead of challenging Sen. Michael Bennet, who Ritter appointed this January when Ken Salazar resigned to join the Obama Cabinet. But Salazar himself could be in the mix as well. A Democratic source tells RCP that the Interior Secretary is being urged by national Democrats to consider running for the seat. Salazar was the state attorney general before being elected to the Senate in 2004.

Scott McInnis is the likely Republican gubernatorial nominee. For its part, the RGA pounced on the Ritter and Cherry news today with this statement:

"The spectacularly early failures of both the Ritter and Cherry campaigns in battleground states ought to send a shiver down the spine of all Democratic candidates for governor this year."