When Mitt Romney was fighting – and losing – "away games" in Southern primaries this month, Illinois always loomed like a breakwall to Rick Santorum's momentum. Tuesday, a big win here could go some way toward doing just that – putting Mr. Romney firmly back on the front foot.
In many ways, Illinois plays to Romney's strengths: It is more politically practical than orthodox, more urban and suburban than rural. But changes in the state make it perhaps less a slam dunk for the front-runner than it might have been in the past, and that has given Mr. Santorum a sliver of hope.
Still, polls show a widening lead for Romney. A Public Policy Poll taken over the weekend showed Romney leading Santorum, 45 to 30 percent. A Chicago Tribune/WGN poll taken 10 days before showed only a 4 point gap.
Clearly, this is nearer home turf for the moderate Romney. The fervor that has inspired conservative Republican voters throughout the South is largely lacking here, say experts. Instead, Illinois Republicans are motivated more by a desire for results than with party purity, says former Illinois Gov. Jim Edgar.
“Illinois politics are not driven by ideology, it’s more pragmatic," says Mr. Edgar, a Republican.
This is primarily a matter of the state's demographics. Polls suggest that the voting dynamics in Illinois are roughly the same as they have been elsewhere. Urban voters favor Romney; rural voters favor Santorum. The difference here is that the math favors Romney.
Some 64 percent of Illinois residents live in or around Chicago. In the 2008 primary, those five Chicago-area counties accounted for 57 percent of the Republican vote.
Another indication of Romney's advantage: only 36 percent of Illinois Republicans identify themselves as evangelical Christians, according to the Public Policy Polling survey. By contrast, exit polling in the Alabama and Mississippi primaries showed that 80 percent of voters were evangelicals.
While Santorum holds a 10 point lead over Romney among Illinois evangelicals, their numbers don't appear to be big enough to turn the tables on Romney.
“In Illinois, as much as Michigan and Ohio, the party is conservative but not Southern conservative,” says Larry Sabato, director of the center for Politics at the University of Virginia in Charlottesville. “The environment is better for a Romney win.”
Santorum must try to overcome the gap by siphoning votes from Romney in the Chicago area and hoping for huge voter turnout in conservative "downstate" areas. He's attempting to do that by aggressively courting the Christian vote.
“I know you don’t get a chance to outvote your friends up in the Chicagoland area very often, but this is a primary and turnout is everything,” Santorum told a crowd in downstate Effingham Saturday.
The get-out-the-vote story is also true for Romney in the Chicago-area counties. But complicating matters is that Chicago's suburban counties are no longer as reliably Republican as they once were, with transplanted city dwellers and Hispanics increasingly moving in. With more independent and Democratic voters in Chicago's collar counties, the suburban Republican core that makes up Romney's base is slowly ebbing.
Turnout in the Chicago area is “the big unknown,” Edgar says.