Looks like the Santorum surge has run its course and Romney will sweep both of today's primaries. The GOP establishment can get down off the ledge, their guy will survive.
Michigan hasn't been called yet, but Karl Rove has been running the numbers based on what's been reported so far and thinks Romney is on his way to a 4-5% win. Certainly as a guy who was born in that state and whose dad was a former governor, you would have expected Romney to win by a wider margin, but two weeks ago he was down 15 points in the polls, and down 5% last week. His advertising effort has clearly paid off.
And the efforts by the left to create a Santorum upset in Michigan have apparently failed. Though the Democrats who voted today have gone overwhelmingly for Santorum there weren't enough of them to make a real difference.
UPDATE: The networks are now projecting Romney the winner in Michigan.