As the Presidential candidates fight for superiority in the polls, George W Bush has sunk to a meagre 26% approval rating. ABC examines the developments and places them in a historical context.

Gary Langer from the ABC peers inside the shifting world of polls:

Barack Obama maintains an advantage on the economy, especially economic empathy, and he’s cracked majority acceptance on his key challenge, experience. But the political center remains unrooted, keeping John McCain in the race, albeit against headwinds. Movement continues among independents, quintessential swing voters and a highly changeable group this year.

McCain’s laboring under the Bush legacy. With the current economic situation, a record 70 percent of Americans disapprove of George W. Bush’s job performance; a career-low 26 percent approve.”

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