Within the down-and-dirty Illinois Senate race between Democrat Alexi Giannoulias and Republican Mark Kirk, there is a critical contest going on, and the goal is to land the broad swath of self-described independent voters.

Some polling data suggests about one in four suburban Chicago voters identify themselves as independent when it comes to party affiliation. And interestingly, these voters are also more likely to disapprove of Barack Obama's job as president.

Kirk calls the suburban voters the "super heavyweights" of Illinois politics. He points out that while some 2.5 million people live in Chicago, in suburban Cook county and the so-called "collar counties" surrounding Cook there 6.5 million people.

And Kirk is more than happy to tell you that between his campaign and the Illinois Republican Party, "We've had more volunteers calling more independent voters of Illinois than any other state. It shows an enthusiasm gap heavily weighted towards the Republican side."

Kirk is also running TV ads touting he is the candidate who will "tax less, spend less and borrow less". It's a message tailored to voters with concerns about federal budgets and spending, and those issues are important to independent voters.

Similar voter contact programs are going on at the Giannoulias campaign and its allies including Organize for America (President Obama's former campaign organization).

Appealing to suburban independents might have been the motivation behind Giannoulias' recent criticism of President Obama. In an interview with the Associated Press, Giannoulias said his friend the president made a mistake by focusing too much on health care and not enough on job creation.

"In a perfect world the administration - folks in Washington - could've done everything they could to spur jobs. (The healthcare battle) took some of the president's political capitol away from where it should've been," said Giannoulias on Tuesday.

Giannoulias adds he's glad the healthcare bill was passed and has said repeatedly he would have voted for it. But distancing yourself a bit from the president is not a bad idea, especially in a tight race where independent voters cool to the administration may decide the contest.

Steve Brown is an author, radio broadcaster and seminary professor at Reformed Theological Seminary in Orlando, Florida.