Washington: The US presidential race had seemed on the verge of slipping from Republican Mitt Romney's grasp a week ago, but now he has erased President Barack Obama's once-substantial lead in polls and made the race for the White House highly competitive once more.
In a clear shift four weeks before Election Day on November 6, a new round of opinion polls showed essentially a dead heat after a strong debate performance by Romney last week.
A Reuters/Ipsos daily tracking poll on Tuesday found Obama and Romney tied among likely voters at 45 percent each, ending a month during which Obama led the survey.
Other polls also reflected the Romney surge. He led by 2 percentage points in Gallup's daily tracking poll and 4 points in a Pew Research Center poll.
Strategists say Obama still holds an advantage in the handful of contested states that will decide the election, but there were signs that Romney may be able to expand the battlefield to states that had been considered beyond his reach.
Pennsylvania and Michigan - regarded until this week as sure bets for Obama - suddenly do not look so safe for him as several polls showed his lead in both states shrinking to 3 percentage points.
A victory in either of those states would multiply Romney's possible pathways to victory and reduce his need to carry make-or-break states like Virginia or Florida.
Both campaigns downplayed the significance of the polls and said they have always believed the race would be close. In one of the most important swing states, Obama urged supporters to register to vote and to get to the polls.
"I need you fired up, I need you ready to go vote. Because we've got some work to do. We've got an election to win," he told some 15,000 people at a rally at Ohio State University.
A CNN poll showed Obama's lead tightening in Ohio to 4 points. No Republican has won the presidency without also taking the Midwestern state.
The plethora of poll results more accurately reflect the dynamic of a closely divided electorate and a lackluster economy, said Ipsos pollster Cliff Young. Obama's earlier wide lead likely would have narrowed regardless of last week's debate.
"Things are probably back to where they should be. This is a race where Romney should be up sometimes," Young said.
In an embarrassment for Democrats, the creators of Big Bird asked the Obama campaign to scrap an anti-Romney ad featuring the popular TV children's character.
Obama's team had used Big Bird to attack Romney for vowing during the debate to cut funding for public television, but is now considering the request to pull the ad.
Romney said the flap showed Obama was not taking his duties seriously. "These are tough times with real serious issues, so you have to scratch your head when the president spends the last week talking about saving Big Bird," he said in Iowa.
With early voting already taking place in some form in 40 states, Obama is trying to mobilize the coalition of minorities, women and younger voters that powered him to victory in 2008.
However, his supporters have grown increasingly distraught in recent days as Obama has largely stayed out of the public eye after his lackluster debate performance.
"I've never seen a candidate self-destruct for no external reason this late in a campaign before," pundit Andrew Sullivan wrote in The Daily Beast.
Romney's speech on foreign policy on Monday is likely to be followed by other policy addresses that lay out his views broadly for those who are only now paying attention to the election, aides said.
The former Massachusetts governor is showing a softer, more personal side on the campaign trail which seems to be working for him.
At a rally in Van Meter, Iowa, he told a story of meeting a young man at a Christmas party who turned out to be one of the former Navy SEALs who died in an attack on the US consulate in Benghazi, Libya last month.
"It touched me, obviously, as I recognized that this young man that I felt was so impressive had lost his life in the service of his fellow men and women," Romney said.
"This is the American way. We go where there's trouble. We go where we're needed. And right now we're needed. Right now the American people need us," he said.