Democratic State Treasurer Alexi Giannoulias and Republican Rep. Mark Kirk will face off for the US Senate seat in Illinois, after both won primary races last might. Kirk won fairly easily against two tea party challengers, while Giannoulias held on against a challenge from Chicago Inspector General David Hoffman, 39-34. If Chicago Urban League President Cheryle Jackson didn’t take so much of the African-American vote, Hoffman may have actually caught Giannoulias, who had a name ID advantage and did well in the Chicago ring counties and downstate.

The gubernatorial races are closer. On the Democratic side, Governor Pat Quinn, who replaced the impeached Rod Blagojevich, held a thin 6,000-vote lead (out of over 800,000 cast) against Comptroller Dan Hynes. Republicans have an even closer race, with State Sen. Bill Brady up only 1,500 votes or so over State Sen. Kirk Dillard with almost everything counted. Expect at least one recount there.

Pollster Tom Jensen notes that 885,000 votes were cast for the Democrat in the Senate primary, compared to 736,000 for the Republican. “Those numbers are awfully close to each other for a state that’s overwhelmingly Democratic,” Jensen said, noting that Barack Obama’s Senate primary in 2004 featured an almost 2:1 split in primary votes.

Other notable races: Denny Hastert’s son Ethan got beat in IL-14 by longtime state lawmaker Randy Hultgren; Dan Seals will try in IL-10 for the third time, just getting by Julie Hamos. Seals lost to Mark Kirk in 2006 and 2008, but IL-10, which trends Democratic, is an open seat this year.