CHARLOTTE, N.C. (AP) -- His re-election in doubt, President Barack Obama aimed to persuade economically strapped middle class America to return him to the White House in a prime-time speech Thursday night closing out the Democratic National Convention.
"Nothing's more powerful than voices calling for change," Obama told supporters on a pre-speech conference call, reasserting ownership of his optimistic slogan from the 2008 campaign after four tumultuous years in office.
The convention's final night also included an acceptance speech from Vice President Joe Biden.
Actress Eva Longoria was on the program, as well. "No empty chairs," she said, a reference to actor Clint Eastwood's mocking reference to Obama at Romney's Republican National Convention last week in Florida.
Convention planners shoehorned a few more seats into the Time Warner Cable Arena for Obama's remarks, pushing capacity to about 15,000. Even so, the decision to scrap plans to hold the night's session in a 74-000-seat football stadium meant a far smaller crowd than the president's campaign hoped would hear him speak and put on an enthusiastic show of support on television.
Officials blamed the switch on weather concerns, and there were heavy rains at mid-afternoon.
Obama's aides said he would use his time on the podium to lay out a second-term approach for the economy, which is struggling through the slowest recovery in generations with unemployment pegged at 8.3 percent.
The economy is by far the dominant issue in the campaign, and the differences between Obama and his challenger could hardly be more pronounced.
Romney wants to extend all tax cuts that are due to expire on Dec. 31 with an additional 20 percent reduction in rates across the board, arguing that job growth would result. He also favors deep cuts in domestic programs ranging from education to parks, repeal of the health care legislation that Obama pushed through Congress and landmark changes in Medicare, the program that provides health care to seniors.
Obama wants to renew the tax cuts except on incomes higher than $250,000, saying that millionaires should contribute to an overall attack on federal deficits. He also criticizes the spending cuts Romney advocates, saying they would fall unfairly on the poor, lower-income college students and others. He argues that Republicans would "end Medicare as we know it" and saddle seniors with ever-rising costs.
With two weeks of big conventions concluding, what will be the ultimate impact?
"You're not going to see big bounces in this election," said David Plouffe, a senior White House adviser. "For the next 61 days, it's going to remain tight as a tick."
The campaign focus was shifting quickly - to politically sensitive monthly unemployment figures due out Friday morning, and the first presidential debate on Oct. 3 in Denver. Wall Street hit a four-year high a few hours before Obama's speech after the European Central Bank laid out a concrete plan to support the region's struggling countries through buying bonds.
Romney wrapped up several days of debate rehearsals with close aides in Vermont and is expected to resume full-time campaigning in the next day or two.
In a brief stop to talk with veterans on Thursday, he defended his decision to omit mention of the war in Afghanistan when he delivered his acceptance speech last week at the Republican National Convention. He noted he had spoken to the American Legion only one day before.
He also said he had no plans to watch Obama on television.
"If the president is going to report on the promises he made and how he has performed in those promises, I'd love to watch it," Romney said. "But if it's another series of new promises that he's not going to keep, I have no interest in seeing him because I saw the promises last time."
It will likely be a week or more before the two campaigns can fully digest post-convention polls and adjust their strategies for the fall.
Based on the volume of campaign appearances to date and the hundreds of millions of dollars spent already on television advertising, the election appears likely to be decided in a small number of battleground states. The list includes New Hampshire, Virginia, Ohio, Colorado, Nevada and Iowa, as well as Florida and North Carolina, the states where first Republicans and then Democrats held their conventions. Those states hold 100 electoral votes among them, out of 270 needed to win the White House.
Money has become an ever-present concern for the Democrats, an irony given the overwhelming advantage Obama held over John McCain in the 2008 campaign.
This time, Romney is outpacing him, and independent groups seeking the Republican's election are pouring tens of millions of dollars into television advertising, far exceeding what Obama's supporters can afford.
"We've got 17 angry, old, white men who are pouring in millions of dollars, carpet bombing every candidate in sight," said Sen. Dick Durbin of Illinois, referring to wealthy Republicans who have written checks for a million dollars or more to Americans for Prosperity and Restore Our Future.
Officials disclosed that former President Bill Clinton, who made a forceful convention speech advocating Obama's re-election on Wednesday night, would campaign aggressively for the Democratic ticket this fall. His first appearance is set for Florida next week.
On Obama's conference call to supporters who were cut out of seeing Thursday night's session, Obama exhorted them to continue their work on voter registration and other pre-election activity.
He said North Carolina is "Exhibit A of the unbelievable work that's being done at the grassroots level. You guys are blowing it up when it comes to registering voters."
Official figures show about 30,000 Democrats have been registered to vote in the state since 2008, but some party leaders said recent canvassing had pushed the actual figure far higher.
On the call, the president commiserated with those who would no longer be able to see him speak.
"The problem was a safety issue. I could not ask you, all volunteers, law enforcement, first responders to subject themselves to the risk of severe thunderstorms," he said.
A few hours later, the skies opened up with a torrential downpour.
