Back in August, a poll showed Obama with just a 12-point lead over Romney in Cook County, Illinois. While he posted a huge lead in the city of Chicago, the poll found him actually losing to Romney in suburban Cook County. It was a shock that I set aside as an outlier.

A new poll of Illinois’ 10th Congressional District, which includes parts of Cook County, however, suggests the August poll might not be such an aberration. The poll, from WeAskAmerica, finds Obama with just a 2 point lead over Romney, 47-45 in the suburban district. Obama won the district in 2008 by 23 points.

I know the district well. It is affluent, with high levels of education, and very socially liberal. Voters there take pride in being politically “moderate” and wear the label as a badge of honor. Since the 1980s, the district has been represented by a Republican in Congress, but not by anyone who could be mistaken for a conservative. Al Gore and John Kerry both carried the district comfortably in 2000 and 2004. And, in 2008, Obama won over 61% of the vote in the district.

Last year, during redistricting, the Democrats in Illinois made the district even more Democrat, looking to unseat freshman GOP Congressman Bob Dold. In this poll, Dold leads his opponent by 2 points, 47-45. It should be noted that this poll was conducted before last night’s debate, so the surprising results don’t reflect Obama’s lackluster performance in Denver.

Obama’s performance in this district in 2008 was emblematic of the appeal he had then to moderates and independents. No Democrat had ever come close to posting the kind of vote he got here. It was also an enormous source of campaign donations for his election. Being essentially tied with Romney, and under the 50% threshold, shows the greatly diminished appeal he has to independents.

“For Mr. Obama to be in a statistical tie in an area that he won by around 20 points in 2008 truly reveals the failure of his Presidency,” said Illinois-based political consultant Paul Miller. “The economy is undoubtedly the key factor, but in suburbs with a large Jewish population, his treatment of Israel is also taking its toll.”

There is a sizable Jewish vote in the district. It could account for the rising dissatisfaction with Obama here. Also a factor could be the lack of leadership from Illinois’ Democrat legislative leaders, who dominate state government and are quickly bankrupting the state. The state’s debt level has exploded and recent massive tax hikes have done nothing to plug the state’s gaping budget deficits.

I should note that the sample in the poll is evenly split between GOP and Dem voters. That may be a bit generous to the GOP, but even this can’t explain the collapse in Obama’s numbers here. A drop of more than 20 points one month out from the election is damning for Obama. Of course, the poll also deliberately oversampled women. They make up around 65% of the poll’s universe. Given the purported advantage Obama has with women voters, his margin in this poll should be considerably higher.

Miller continued: “Unfortunately for the GOP, they wrote off Illinois before the campaign season began. Considering that President Obama may under-perform by a large percentage, and that his numbers in Cook County are not nearly as strong as they were four years ago, Illinois could have been in play. It may not be too late to make Illinois purple.”

Given the state of the GOP in Illinois, I’m not certain Romney could have made Illinois competitive this year. Certainly, Obama continues to have the edge in his adopted home state. But, among the base of some of his core supporters, the thrill is clearly gone.

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