Unity is a challenge not just for Obama but for the Republicans, who won less than 30 percent of the growing Hispanic vote and not even one in 10 black voters. Obama built a strong Electoral College majority, if only a narrow advantage in the popular vote, despite losing every age group of non-Hispanic white voters.
Surveys of voters found Obama's health care law to be as divisive as ever, with just under 50 percent wanting it repealed in whole or part, and 44 percent liking it as is or wanting more of it.
But democracy doesn't care about exit polls, either, and the election almost certainly means Republicans can forget about trying to roll it back now.
In reaffirming divided government, though, Americans all but ensured colossal fights are ahead over the shape of government and Obama's agenda. He is out to break a wall of Republican opposition to tax increases on the wealthy — a move that about half the voters in exit polls thought was a good idea. And extraordinarily difficult negotiations are imminent as the president and Congress try to make a deal to avoid the "fiscal cliff" — steep spending cuts and a variety of tax increases in January.
In the end, voters split about equally on whether Obama or Romney would be better at handling the economy.
Then again, they were divided down the middle on whether Obama or his predecessor, George W. Bush, deserves most of the blame for the economy's problems.
So it goes in the 50-50 nation, give or take.
Associated Press writers Christine Armario in Miami, Michael Tarm in Chicago, David Martin in New York, Amanda Myers in Cincinnati and Ann Sanner in Columbus, Ohio, contributed to this report.
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