What did Barack Obama win for?

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 other reason was widespread disapproval of the invasion of Iraq.