US voters are nearly evenly divided between President Barack Obama and Republican challenger Mitt Romney with five months to go before the election, especially on handling the economy, polls show.
With US unemployment still hovering above 8%, both candidates have stepped up their emphasis on jobs and the economy. Obama and Romney have offered a starkly differing vision of how the economy should work as they appeal to voters who say jobs are the foremost issue in the November election.
A new Washington Post-ABC News poll shows Obama and Romney locked in a dead heat over handling the economy. They are tied at 47%.
Overall, 49% said they back Obama for re-election and 46% preferred Romney, a statistically insignificant difference.
Other recent national polls show a similarly close margin.
Earlier polls generally showed the former Massachusetts governor holding a slight lead over Obama on economic issues and Obama slightly ahead overall.
But the tightening follows an aggressive attack on Romney's business credentials by the Obama campaign, including ads painting him as a job-destroying corporate raider at Bain Capital, the private-equity firm he co-founded.
Romney called the attacks "character assassination". But Obama suggested Romney's background was a poor qualification for the White House since being president involves more than "maximising profits".
The survey found that 80% of Americans still hold a negative view of the economy, but 54% said they felt more positively about the economic situation in the coming years, and 58% felt the financial prospects would improve.
An NBC-Wall Street Journal poll, meanwhile, suggested that Obama's endorsement of gay marriage two weeks ago was a political wash, with 17% saying it makes them more likely to vote for him and 20% saying it makes them more likely to vote for Romney, who opposes gay marriage.