File Photo, Image Credit: Flicker User comedy_nose , via CC

The President and Vice-President of the US are elected every four years.
The Political Parties amongst themselves choose their candidates to run for president and vice president.

Last time the elections were held in 2008 where Illinois Senator Barack Obama from the Democratic Party went to become the first African American president in the history of United States.

In 2012, Barack Obama is contesting for a second term of the presidency against Republican Party Presidential Candidate Mitt Romney.