Presidential transition of Barack Obama time of their election, President-elect Obama and Vice President-elect Joseph Biden were incumbent U.S. Senators from Illinois and Delaware respectively. In accordance with Article I, Section 6 of the United States Constitution, both were required to resign their respective Senate seats on or before January 20, 2009, in order to become President and Vice President. Obama resigned from the Senate effective November 16, 2008. Initially, it was thought that his replacement would be named by Illinois Governor Rod Blagojevich. Since the term for the seat expired in January 2011, it would come up for its normal election in 2010 with
Vice President of the United States became moot. In the 2008 Democratic presidential primaries which pitted Hillary Clinton against Barack Obama, Clinton suggested a Clinton-Obama ticket with Obama in the vice president slot as it would be "unstoppable" against the presumptive Republican nominee. Obama rejected the offer outright saying "I want everybody to be absolutely clear. I'm not running for vice president. I'm running for president of the United States of America" while noting "With all due respect. I won twice as many states as Sen. Clinton. I've won more of the popular vote than Sen. Clinton. I have more delegates than Sen. Clinton. So, I