From NBC's Mark Murray
Illinois Attorney General Lisa Madigan -- who was mulling a possible Senate or gubernatorial bid in 2010 (and had been speaking with the Obama White House about these races) -- has instead decided to run for re-election, according to a Democratic official.
The news is a blow to the White House and the Democratic Senatorial Campaign Committee, since Madigan was widely viewed as the Democrats' top choice for Barack Obama's old Senate seat that's now filled by the embattled Roland Burris.
With Madigan's decision, the top possible Democratic contenders for the Senate seat are Chris Kennedy (Robert F. Kennedy's son) and state Treasurer Alexi Giannoulias. Burris also may or may not run.
The Republicans top potential candidate is Illinois congressman Mark Kirk, but he has not yet decided whether he'll jump into the race.
Democrats insist they're still poised to hold on to this Senate seat in deep-blue Illinois, even after the Blagojevich scandal that ended up propelling Burris into Obama's Senate seat. Still, Kirk's ultimate decision will tell us much more about how competitive this Senate race will be next year.
*** UPDATE *** Per the Washington Post Cillizza, who broke this story: "To be clear, Madigan would have been a favorite had she decided to run for either the Senate or for governor, a fact that makes her decision to run for neither office all the more puzzling."