Dirty Trick'?: Santorum's Surprise Robocall to Michigan...Democrats?

Rick Santorum is pulling out all the stops in hopes of a Michigan victory. The former Pennsylvania Senator released a robocall today specifically targeted at Democratic/union voters in Michigan's primary.

"On Tuesday, join Democrats who are going to send a loud message to Massachusetts Mitt Romney,” the ad says. "Romney supported the bailout for his billionaire buddies but opposed the auto bailout. That was a slap in the face to every Michigan worker.”

And if anyone is in any doubt as to the source of this ad, it ends with, "This ad is supported by hard-working Democratic men and women and paid for by Rick Santorum for President."

The full robocall can be heard here:

This marks Santorum's first attempt at picking up the "Reagan Democrats" , to whom he has repeatedly claimed he has the ability to appeal. Whether it will win support from conservatives is another story, as it arguably undercuts Santorum's swipe at Romney in last week's debate for "adopting the Occupy Wall Street rhetoric."

Certainly Romney isn't taking it lying down. The Associated Press reports that Romney has already slammed Santorum for the call:

Republican presidential candidate Mitt Romney is accusing his main rival, Rick Santorum, of pulling a "dirty trick" by sponsoring a computerized phone call urging Michigan Democrats to vote against Romney in Tuesday's Republican primary. [...]

The "robocall" going around Monday says Democrats should send "a loud message" to Romney by voting for Santorum. The message says it's supported by "hard-working Democratic men and women" and paid for by the Santorum campaign.

Romney tells Fox News that the robocall sounds like it's coming from organized labor, and he says the effort is confusing people and deceptive. Romney calls it "a new low" in the campaign.