Pritzker was an early supporter of Obama's political career, helping to finance his 2004 Senate campaign. Early in the Democratic presidential primary, Pritzker's financing helped Obama's candidacy survive when Obama was trailing Hillary Clinton in the polls. Pritzker remained a major fundraiser for Obama during the 2008 Democratic primary and raised millions overall for his White House bid. She served as the national finance chair of Obama's 2008 presidential campaign. Under her direction, the campaign reached out to small donors. Pritzker also hosted more lavish fundraisers as part of her effort to raise money.