CHICAGO - Barack Obama wasn't supposed to win re-election. The hope was gone, critics said, evaporated by endless partisan gridlock in Washington and a jobless rate that hovered above 8 percent for much of his first term.

And yet, a relentlessly focused campaign, a flicker of economic good news - witnessed in rebounding consumer confidence - and a prolonged assault on his opponent persuaded voters to give the Democrat who made history in his 2008 election another four years in office.

In campaign stops across battleground states, Obama pressed for patience, arguing that he'd prevented an economic collapse and that under his stewardship the economy was beginning to recover.

In every speech, he laid siege to his Republican rival, cautioning that Mitt Romney would return the United States to the same failed policies that plunged the economy into a downward spiral.

The survey of voters as they left polling places Tuesday showed six in 10 voters say the economy is the top issue facing the nation, with unemployment and rising prices hitting voters hard. But about half of voters say former President George W. Bush is more responsible for the economic challenges than Obama, according to an exit poll conducted for The Associated Press.

In the end, the former Massachusetts governor failed to convince enough voters he was on their side - a story line the Obama campaign pursued with a single-minded focus before Romney had even clinched his party's nomination.

The portrait of Romney that emerged was of an elite executive who led a private equity firm that drove jobs overseas and cut employment in the United States.

"One thing they've done well is trash Mitt Romney," said Whit Ayres, a Republican political consultant who co-founded a polling firm. "They've done a stellar job running an exceedingly personal campaign against Mitt Romney."

Democrats say Obama was able, despite the sluggish economy, to point to achievements. He trumpeted success at preventing the economy from hitting bottom with a stimulus plan that plowed government dollars into hiring.

He achieved long-sought health-care legislation, enacted a firewall to prevent a relapse of the Wall Street fiasco, backed a federal bailout to save auto industry jobs, ended the war in Iraq and oversaw the raid that ended in the death of Osama bin Laden.

"Osama bin Laden is dead and General Motors is alive," Vice President Joe Biden suggested as an Obama campaign bumper sticker. "That about sums it up, man."

At the close of the election, Obama was boosted by a crisis beyond any candidate's control. As the storm Sandy barreled up the East Coast, Obama suspended his campaign appearances to tend to the emergency response, projecting an air of confidence and compassion.