Mitt Romney accused Rick Santorum of being “deceptive” and taking the Michigan primary to a “new low” by encouraging Democrats to vote for him against Romney in a robocall released yesterday.

“Senator Santorum did something today which I think is deceptive and a dirty trick,” Romney told Sean Hannity last night. “He’s put an ad out their, sounding like a labor ad, telling Democrats to go out there and vote against me and to vote for Rick Santorum, and at the very end there’s a little trailer that he paid for this. But it’s confusing people — it’s a new low in this campaign.”