Columbia subject headings:
Elections--United States.
Obama, Barack.
Political campaigns--United States.
Presidential candidates--United States.
Presidents--United States--Election--2012.
Romney, Mitt.
United States--Politics and government--2009-2017.
Voting--United States.
Harvard subject headings:
Elections--United States
Obama, Barack
Political campaigns--United States.
Presidential candidates--United States
Presidents--United States--Election--2012.
Romney, Mitt.
United States--Politics and government--2009-2017.
Voting--United States
Princeton subject headings:
Elections--United States.
Obama, Barack.
Political campaigns--United States.
Presidential candidates--United States.
Presidents--United States--Election--2012.
Romney, Mitt.
United States--Politics and government--2009-.
Voting--United States.