2012 Democratic Party presidential primaries
From January 3 to June 5, 2012, voters of the Democratic Party chose its nominee for president in the 2012 United States presidential election. President Barack Obama won the Democratic Party nomination by securing more than the required 2,383 delegates on April 3, 2012, after a series of primary elections and caucuses.
Source: Wikipedia — 2012 Democratic Party presidential primaries (CC BY-SA 4.0)