Claim: Republican candidate Mark Kirk won by a landslide over Alexi Giannoulias of the Demcrats at the 2010 United States Senate elections in Illinois, the last Republican to win in Illinois as of 2020.
Evidence: Mark Kirk Alexi Giannoulias 1,677,729 1,641,486 1,778,698 1,719,478 A landslide victory is an election result in which the victorious candidate or party wins by an overwhelming margin. Even within an electoral system, there is no consensus on what sized margin makes for a landslide. As of 2020, this is the last time a Republican won a U.S. Senate election in Illinois.