"2008 Democratic primaries" . . "Democratic primaries of 2008" . "2008 Democratic Primary campaign" . "primary" . "2008-06-03" . "eight years prior" . "2008 Democratic rival" . "2008" . "2008 Democratic nomination" . "violations of scheduling rules" . "Democratic nomination" . "Democratic primary" . "2008 presidential primary" . "Democratic presidential primary" . "Democratic primaries" . "his candidacy for president" . "2008 Democratic primary" . "his candidacy in the 2008 elections" . "Democratic Primary in 2008" . "2008 Democratic presidential primaries" . "Democratic nomination in 2008" . "running against Hillary Clinton" . "2008 election" . "Democratic Party primaries" . "eight years earlier" . "2008 Nevada caucuses" . "2008 Democratic Party presidential primaries" . "2008 Democratic Party presidential primaries" . "Primary" . "2008 Democratic presidential primary" . "Democratic presidential preference primary" . "Biden's 2008 presidential campaign" . "2008 Democratic party primary elections" . . "2007\u20132008 presidential primaries" . . . "unsuccessful campaign" . "2008 Democratic presidential candidate" . "Democratic nomination for President" . "Democratic presidential nomination" . "2008 Democratic Party presidential primaries" . "2008 Democratic primary campaign" . . "a close primary campaign" . "Democratic primary race" . "Democratic Party presidential primaries" .