The 2010 U.S. Senate race in Illinois is now a dead heat between the top Democratic and Republican contenders.

The latest Rasmussen Reports telephone survey in the state finds Republican hopeful Mark Kirk tied with Democratic State Treasurer Alexi Giannoulias 41% to 41%. Only four percent (4%) would choose another candidate, while 13% remain undecided.

In mid-August, Kirk held a modest 41% to 38% over Giannoulias.

Women in Illinois prefer the Democrat by a 43% to 38% margin, while men choose Kirk 45% to 39%.

Voters not affiliated with either major party prefer Kirk by more than two-to-one - 52% to 23%.

Giannoulias is considered the favorite in the February 2 Democratic Primary to win the nomination for the seat once held by Barack Obama. Roland Burris, the Democrat named to the seat by since-impeached Governor Rod Blagojevich following Obama’s election as president, has been embroiled in controversy ever since and has announced he will not seek election to a full six-year term.

Kirk, the most prominent Illinois Republican in the race at this time, is now serving his fifth two-year term as the U.S. congressman representing the northern suburbs of Chicago. He is on course at this time to get the GOP Senate nomination despite unhappiness from some conservatives in his party. Still, Kirk faces an uphill climb in a state that has been running Democratic in statewide races for some time now.

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But Giannoulias hasn't wrapped up the race on his side of the fence yet, and the race is heating up between Kirk and another possible Democratic contender. Kirk's lead over Cheryle Jackson, a former top aide to Blagojevich, is now down to four points - 43% to 39%. Kirk led Jackson by 17 points in August. Only four percent (4%) now say they would vote for another candidate given that match-up, and 13% are undecided.

Once again, unaffiliated voters in Illinois pick Kirk over Jackson by a substantial 52% to 19% margin.

Kirk also leads another Democratic hopeful, former Chicago Inspector General David Hoffman, 43% to 33%. Sixteen percent (16%) are undecided on this match-up, while another eight percent (8%) favor a different candidate.

Eighteen percent (18%) of Illinois voters have a very favorable opinion of Kirk, while eight percent (8%) regard him very unfavorably. Giannoulias is viewed very favorably by 17% and very unfavorably by 14%. These numbers are up slightly for both candidates from August. Roughly one-out-of-five voters don't know enough about either man to venture even a soft opinion about him.

Jackson is regarded very favorably by 14% and very unfavorably by 16%, virtually unchanged from August. In her case, 30% have no opinion. As for Hoffman, his very favorables total five percent (5%) while his very unfavorables are 10%. Nearly half of Illinois voters (48%) have no opinion of him.

At this point in a campaign, Rasmussen Reports considers the number of people with a strong opinion more significant than the total favorable/unfavorable numbers.

The vast majority of Illinois voters (89%) believe their state’s politicians have no done enough to clean up politics after the Blagojevich scandal. Only six percent (6%) say they have done enough.

Fifty-five percent (55%) of Illinois voters somewhat or strongly approve of President Obama’s job performance so far, showing little change from August. Forty-four percent (44%) disapprove of the job their former senator is doing in the White House. Obama’s approval ratings in Illinois are well ahead of those found on the national level in the Rasmussen Reports daily Presidential Tracking poll.

We will release new numbers on the 2010 governor race in Illinois later this week.

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