According to Rasmussen Reports' analysis of their latest statewide Illinois poll, the U.S. Senate race remains very close.  Below are the toplines from the new poll (with the results of the four previous Rasmussen surveys in parentheses):

Giannoulias: 43% (40%, 39%, 38%, 37%)

Kirk: 41% (39%, 42%, 46%, 41%)

You can check out TPM's polltracker for the race here.