Rasmussen has a poll out today showing Mark Kirk ahead of Alexi Giannoulias by four points in the Illinois Senate race, with 45 percent supporting Kirk, 41 percent supporting Giannoulias and 4 percent supporting Green Party candidate LeAlan Jones.

While these raw numbers aren’t dramatically different from last week, when Kirk posted a three-point lead over Giannoulias, two things stand out.

First, Kirk’s pushing Rasmussen’s four-point margin of error. Second, this is the first set of poll results where, if the Green Party candidate’s voters broke for Giannoulias, the race would be a tie rather than a Giannoulias victory. Kirk’s attacks may be having an effect, as may the recent revelation that Giannoulias can’t name a single piece of spending he wouldn’t have voted for.