Rick Santorum’s campaign has acknowledged that they are making robocalls to Michigan Democrats, encouraging them to vote in today’s open primary. With the race so tight — and Santorum’s Monday night lead due to his whopping 37 point lead among Democrats who might vote in today’s primary, according to Democratic firm Public Policy Polling — it’s possible that Democratic voters could deliver Santorum a win. Mitt Romney is outraged by Santorum’s tactics, reports NBC News:

Santorum’s effort to turn out Democrats against Romney was clearly a focus of his appearance this morning. Romney dispensed with the usual made-for-TV hallmark of his primary-day events: He never picked up a phone to call undecided voters. Instead, upon arriving with Michigan Gov. Rick Snyder in tow, he joked with his own volunteers.
“You are making calls to Republicans today. This is a good thing, all right,” Romney said drily. “The Santorum campaign is making calls to Democrats today.”
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“I think Republicans have to recognize there’s a real effort to kidnap our primary process,” Romney said. “And if we want Republicans to nominate the Republican who takes on Barack Obama, I need Republicans to get out and vote and say no to the … dirty tricks of a desperate campaign.”