Throughout the republican primary campaign, Newt Gingrich and Rick Santorum have hurt each other's chances as they aspire to be "the conservative alternative to Mitt Romney."
The dynamic in Illinois is somewhat different. That Gingrich, a well-known brand among mainstream republicans here, might hurt Romney more than Santorum.
For the second day in a row, Gingrich targeted voters in party leaders say should be Romney country: Chicago's northwest suburbs. The former speaker appeared Thursday morning at Judson University, a small evangelical Christian college in Elgin.
"A one-sided appeasement of radical Islam while crushing Christianity and Judaism strikes me as exactly what's wrong with America today," Gingrich said at the event.
Gingrich told me during our one-on-one interview that his goal for the next six months is to stop delegate leader Mitt Romney before the Tampa convention.
"If Romney doesn't win, Santorum's not gonna have a majority," Gingrich said. "I'm not gonna have a majority. We're going to be in the most open political process in your lifetime you've ever covered. It will be a newsman's dream."
The former Massachusetts governor has scheduled a campaign stop near O'Hare tomorrow morning several hours before his nearest challenger Rick Santorum appears in Arlington Heights.
"Everybody duke it out 'til the nomination and they'll come together at the end anyway," said voter Michael Frushour.
Some voters said that contrary to what's happened in other states, the well-known Gingrich staying in the race will hurt Romney.
"If the speaker were not in the race, I definitely would go with Mitt Romney," said Gingrich supporter Eligio Marin.
Campaigners for Governor Romney, supported by the Illinois Republican Chairman, Senator Mark Kirk and State Treasurer Dan Rutherford, say Illinois is critical for re-establishing the front-runner's momentum.
His supporters are hoping that Gingrich's appeal to mainstream republicans in Illinois will take enough votes away from Romney to prolong the race.
"Hopefully, it will go to the convention and the convention delegates will get to decide," said T.R. Smith. "I would like to see Newt stay in until the convention and who knows what can happen at the convention."
Governor Romney suddenly scheduled the stop Friday morning at a diner near O'Hare Airport. He and/or a political action committee already have a full slate of TV ads around the state.
From the other side, Chicago Mayor Rahm Emanuel blasted Romney for not being more critical of what he called talk radio host Rush Limbaugh's "repulsive comments" about a female law student.
"If you can't stand up to Rush, how are you going to stand up to Russia?" Emanuel asked.
Santorum has an event tomorrow afternoon in Arlington Heights. While the former Pennsylvania senator's campaign does not have delegates on the ballot in four of the state's eighteen congressional districts, it still believes a Santorum popular vote victory is within reach.
The political eyes of the nation, at least the Republican ones, are watching what happens in Illinois between now and next Tuesday.