 On July 26, 2009, Giannoulias announced his candidacy in the 2010 election for the seat in the United States Senate held by Roland Burris.Burris, who was appointed by Governor Rod Blagojevich to fill the seat vacated by Barack Obama following Obama's election as President of the United States, chose not to seek election.Giannoulias won the Democratic primary on February 2, 2010, then faced Republican Mark Kirk as well as Green Party candidate LeAlan Jones and Libertarian Michael Labno in the general election in November 2010.