Feds say a Texas doctor perpetrated biggest Medicare scam in U.S. history.

Reports emerging in the last few minutes that Sen. Olympia Snowe (R-ME) will not seek re-election this year. As far as I know, this news comes completely from left field, with Snowe previously expected to cruise to re-election. It sets up a prime opportunity for Democrats to pick up a seat and perhaps hold on to their majority. Not immediately clear who the most likely Democratic contenders will be. Or the Republican ones for that matter. More on that shortly …

Olympia Snowe’s resignation statement reads like an application for membership in the club of professional DC centrist handwringers:

As I enter a new chapter, I see a vital need for the political center in order for our democracy to flourish and to find solutions that unite rather than divide us. It is time for change in the way we govern, and I believe there are unique opportunities to build support for that change from outside the United States Senate. I intend to help give voice to my fellow citizens who believe, as I do, that we must return to an era of civility in government driven by a common purpose to fulfill the promise that is unique to America.

Queue the paeans to Snowe’s statesmanship.

Evan McMorris-Santoro talks to Michigan Democratic voters wrestling with whether to sow chaos by voting for Rick Santorum.

How the RNC deliberately engineered an extended primary calendar only to see it backfire.

Rick Santorum, January 29, 2012: “If you’re a Democrat and you want to be a Democrat, then vote in the Democratic primary, not the Republican. If you want to vote in the Republican Party then become one.”

President Obama: “These are the folks who said if we went forward with our plan to rescue Detroit, ‘you can kiss the American automotive industry goodbye.’ Now they’re saying they were right all along!”

Olympia Snowe’s surprise decision not to seek re-election this year caught Maine and Washington completely off guard. The parties are scrambling tonight to line up viable candidates for the seat, with the filing deadline barely two weeks away.

We’ve got the audio of another robocall in Michigan that went out today and appears to be from the Santorum camp, urging Dems to cross over and vote against Mitt.

When the results start coming in in Michigan, we’ll have them right here on our county by county results page. Right here.

For the very latest updates of everything that goes down tonight, check out TPMLiveWire.