By John Whitesides
CHARLOTTE, North Carolina (Reuters) - President Barack Obama and Republican challenger Mitt Romney launch a two-month sprint to the November 6 election on Friday, hours after Obama closed the Democratic convention with an urgent plea for more time and patience to finish his economic agenda.
Obama's high-stakes nationally televised acceptance speech for a second term capped two weeks of back-to-back nominating conventions for Obama and Romney.
The address opened the last phase of a White House battle that polls show is essentially deadlocked amid deep voter concerns about the economy, which the president argued he had put on the road to recovery even though growth remained lackluster.
Both candidates will hit the campaign trail on Friday hours as the U.S. Labor Department releases its jobless report for August, a crucial economic indicator that both camps are watching anxiously.
With unemployment remaining at a stubbornly high 8.3 percent nationally, even a slight shift could strengthen the economic arguments for either Romney or Obama during a campaign dominated by the debate about job creation.
A rise in unemployment would boost Romney, the former head of a private equity firm who has made his business experience the centerpiece of his campaign. He argues he is uniquely qualified to create job growth and says Obama is not up to the job.
But a dip would bolster Obama's case that job growth is moving in the right direction, even if it has taken longer than expected to turn the economy around.
Private employers added 201,000 jobs in the month of August while jobless benefits fell last week in a potential sign of a slightly improving jobless rate.
'NO GREAT SHIFTS'
"Despite the frenzy of the conventions, Friday's jobs numbers should not result in great political shifts despite great political scrutiny," Republican strategist Tony Fratto said in a note to clients.
Obama and Vice President Joe Biden head on Friday to the toss-up states of Iowa and New Hampshire for joint campaign events. Romney also will head to those two states, which could be critical to piecing together the 270 electoral votes needed to win the White House.
They are among eight to 10 battleground states that are likely to decide the election, a list that also includes Florida, Virginia, North Carolina, Ohio, Colorado, Nevada and Wisconsin.
Those states have been flooded by tens of millions of dollars in television advertisements by the campaigns, and hundreds of millions more from outside groups allied with both candidates.
The Romney camp announced that it would release 15 new television ads on the economy, called "A Better Future," in eight states on Friday - Colorado, Florida, Iowa, Nevada, New Hampshire, North Carolina, Ohio and Virginia.
Polls show the economy is the top issue for voters, and Obama addressed their anxieties head on in his acceptance speech on Thursday.
"You elected me to tell you the truth, and the truth is, it will take more than a few years for us to solve challenges that have built up over decades," he said.
"But know this, America: Our problems can be solved. Our challenges can be met. The path we offer may be harder, but it leads to a better place."
Republicans were unimpressed.
"Americans will hold President Obama accountable for his record - they know they're not better off and that it's time to change direction," Romney campaign manager Matt Rhoades said in a statement.
The Obama speech, moved indoors to a 20,000-seat basketball arena after threats of severe weather canceled plans to hold it in a 74,000-seat football stadium, in many ways failed to capture the energy and excitement of his 2008 nomination in Denver.
But Democrats said they were pleased with the three-day convention, which also featured energetic speeches by first lady Michelle Obama and former President Bill Clinton that galvanized the crowd and sent Democrats home with a renewed energy for the fall campaign.
"That was inspiring. I'm more motivated than I've ever been," Azziem Underwood, a delegate from Renton, Washington, said after Obama left the stage.
With the conventions out of the way - Republicans met last week in Tampa, Florida - the next big event on the political calendar is the first of three presidential debates on October 3 in Denver.
Vice President Joe Biden and Republican vice presidential contender Paul Ryan also will meet in one debate on October 11 in Danville, Kentucky.
(Editing by Alden Bentley)