What made Barack Obama president?

Incumbent Presidents usually get the credit or the blame for the economy. In 2008, the incumbent, George W. Bush, wasn't running for reelection. However, Barack Obama's opponent, John McCain, was largely seen as Bush's successor. So, McCain suffered the backlash when the financial markets crashed less than two months before the election. In other Words, to quote President Bill Clinton, "It's the economy …."

The second reason for Obama's victory was widespread disapproval of Bush's invasion of Iraq.