Republican presidential contender Rick Santorum declared himself a conservative "heavyweight" on Tuesday as he defended his decision to court Michigan Democrats in the state's high-stakes GOP primary.
"I am the heavyweight in this race when it comes to moving this country in the conservative direction," Santorum told reporters while visiting a campaign call center several hours before local polls closed.
Romney "is a lightweight on conservative accomplishments, which happens to be more important than how much success and how much money you've made in business," he said.
Earlier in the day, Romney fueled the intensifying war of words by calling Santorum "an economic lightweight."
Both candidates campaigned on opposite ends of Romney's home state as local voters decided what may be a pivotal primary contest. Recent polls suggest the race is a toss-up. Arizona also holds its GOP presidential primary Tuesday and Romney is favored to win.
The Michigan contest took a turn on the eve of the election when Santorum's campaign used automated telephone calls to encourage Democrats to vote against Romney.
Romney complained that the tactic is "deceptive and a dirty trick."
Santorum, a former Pennsylvania senator, suggested that Romney did much the same thing when he courted independent voters in New Hampshire's GOP primary last month.
He also accused the former Massachusetts governor of employing his own "dirty trick" by running automated calls that featured a 2008 recording of Santorum endorsing Romney for that year's primary election. And he noted that Ronald Reagan courted Democrats in Texas during his 1976 presidential campaign.
Santorum suggested that Romney should stop with the complaints.
"I didn't complain about it. I don't complain. You know what? I'm a big guy. I can take it," Santorum said outside a Grand Rapids-area restaurant Tuesday morning. "We're going to get voters that we need to be able to win this election. And we're going to do that here in Michigan today."
Only Michigan Republicans may vote in Tuesday's GOP primary, but party rules allow voters to change their affiliation temporarily on the spot.
Santorum's automated message says Democrats should send "a loud message" to Romney by voting for Santorum.
Romney said the tactic was "a new low" in the campaign.
"I wasn't too concerned about what the Democrats were putting out there because I figured it wouldn't have much impact. But Sen. Santorum did something today which I think was deceptive and a dirty trick," Romney said on Fox News.
Santorum made two appearances at local restaurants near Grand Rapids early Tuesday, a city set in a western Michigan region home to many of the social conservatives and tea party supporters he is courting. Accompanied by his wife, Karen, Santorum shook hands for a few minutes at each stop, but did not say much beyond thanking the sometimes unsuspecting diners for being there. He did not ask for anyone's vote.
At a subsequent stop at a Grand Rapids campaign call center, Santorum and his wife spoke to a few supporters by phone and encouraged them to get out the vote. After he left, just a handful of volunteers remained to make calls.
Santorum's recent rise to prominence in the GOP presidential contest has been fueled by a continued reluctance among the GOP's more conservative voters to embrace Romney.
"I don't trust him," Carol Alexander of nearby Wyoming, Mich., said of Romney while waiting for Santorum to arrive at the Rainbow Grille in Grandville, Mich.
A self-described religious conservative, she said she leaned toward Santorum, who she said "speaks what he believes."
Alexander said she's been inundated with phone calls from campaigns, adding that "it's been getting kind of nasty." But she discounted the impact of Santorum's latest tactic.
"Do you really think a liberal is going to vote for Santorum?" she asked with a smile. "I don't think they're going to do it."
The stakes in Michigan may be higher for Romney, who was born and raised in Michigan. His father served as the state's governor in the 1960s.
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