Republican Mark Kirk Defeats Alexi Giannoulias in Illinois Senate Race

Nov. 3, 2010— -- Republican Congressman Mark Kirk will defeat Democrat State Treasurer Alexi Giannoulias in the bitterly contested race for the Illinois senate seat that launched Barack Obama to the White House, ABC News is projecting.

For Republicans, a victory in the Land of Lincoln represents a symbolic trophy in their efforts to wrest control of Congress from Democrats.

The race had been fraught with claims of dishonesty on both sides, leading to an exceptionally high level of distaste for both candidates, according to preliminary exit polls.

Of the 37 closely-watched Senate contests across the country, this was one of the nastiest, with Giannoulias portrayed as a mob banker and current Kirk as a serial liar.

The acrimony was reflected in preliminary exit poll results, with a third of the voters saying they felt neither candidate was honest and trustworthy. More than half the voters said both candidates attacked each other unfairly.

Further, more than half expressed either reservations about their candidate or said their vote simply reflected their dislike for the other candidate.

The outcome would have been inconceivable just two years ago as Democrats watched their favorite son carry the state by 25 points to win the presidency and the party sweep Republicans from every statewide office.

But then came the scandal and corruption trial involving former Gov. Rob Blagojevich, the national economic collapse, the controversial stimulus package and the debilitating fight over healthcare that transformed the political landscape.

Aware of Illinois' symbolic importance, Obama had sought to protect his seat with three visits to his home state, including one last weekend. Both the president and the first lady worked to keep the seat blue, appearing at fundraisers and in a campaign ad for Giannoulias, the 34-year-old state treasurer and self-styled Obama protégé.

But Illinois voters appeared split almost evenly on Obama's performance as president, according to the preliminary exit poll results. And a third said their vote for senator was specifically to express opposition to Obama.

About as many, though, said they were voting explicitly to show support for him.