The five-term congressman said Monday this gives him $2.3 million in the bank for the February primary election.
It's not clear how much money other Senate candidates have raised so far. Official reports come out later this month.
In the Republican primary, Kirk faces several little-known candidates. They'll have a hard time coming close to his fundraising levels.
The Democratic candidates may have more fundraising strength. The candidates include state Treasurer Alexi Giannoulias, Cheryle Robinson Jackson of the Chicago Urban League and David Hoffman, Chicago's former inspector general.