By BEN FELLER, AP White House Correspondent
CHARLOTTE, N.C. (AP) — To a nation short on job security, President Barack Obama has his night to protect his own.
Obama's speech at the Democratic National Convention on Thursday will be about promise - the kind he'll say he has kept, and the kind of feeling he wants to stir once more. He will take people back to the start of his presidency to make a case why their lives are better, but his bigger imperative is to sell himself as better for middle-class America than Republican Mitt Romney.
Gone is the newness of the last time he stood up to accept the nomination of his party. Obama, the graying incumbent, will not try to recreate it.
Instead, he will whittle the election down to a choice, spelling out his vision of how to create economic opportunity for all, and warning that Romney would restore trickle-down ideas that Obama says were quietly gutting the economy for years before crashing it completely.
That's the policy part. Obama will also try to summon inspiration again that America is right on the cusp of what it could be.
Campaigns can thrive or die on voter passions, and Romney had his shot at this first. At his own convention last week, he told a TV audience of millions that it was a telling sign if many people's best feelings about Obama peaked the moment they voted for him.
Gone, too, is the setting Obama wanted for the biggest address of his re-election bid.
Democrats opted for their convention's rented basketball arena instead of a much larger, open-air football stadium for Obama, wary of the safety and political risks if rain came pouring down.
"We can't let a little thunder and lightning get us down. We're going to have to roll with it," Obama said in a phone call to supporters who lost their chance to attend because of the site switch.
Yet tighter, packed quarters of energized supporters could present just the optics Obama wants on TV. He must give his backers and undecided voters a reason to mobilize behind him.
It worked on Wednesday night for former President Bill Clinton, and for first lady Michelle Obama the night before that.
Both of them signaled precisely where Obama will be headed in his own speech.
In a nation in which more than 23 million people are unemployed or underemployed, Obama will focus instead on the millions who have found work, and how many more can, too. He will talk of education and energy and innovation and job training.
He will ask for more time.
As Clinton put it: "No president - not me, not any of my predecessors - no one could have fully repaired all the damage that he found in just four years. But he has laid the foundations for a new, modern, successful economy of shared prosperity. And if you will renew the president's contract, you will feel it."
Obama's speech will cover the dominant themes of his campaign. Those will include government as an enforcer of fairness and consumer protection, leadership as demanding compromise with the other party, financial stability as requiring that rich people pay more taxes.
He will likely portray Romney, who made a fortune in business, as so focused on limited government that he would leave people to struggle on their own and to hope for the best.
"Barack knows the American dream, because he's lived it," Michelle Obama said. "And he wants everyone in this country, everyone to have the same opportunity, no matter who we are or where we're from or what we look like or who we love. And he believes that when you've worked hard, and done well and walk through that doorway of opportunity, you do not slam it shut behind you."
Obama was spending much of Thursday out of public sight at his hotel. He spent some time with his wife and then fine-tuned his speech with aides.
In speaking for seven minutes to the supporters shut by the stadium switch, Obama promised he was poised to deliver a clear contrast to Romney, and implored the volunteers to "prove the cynics wrong one more time."
By night's end, he wants teetering voters to emerge with two takeaways about him - a sense that he made tough decisions, and a sense of clarity about what he would do in a second term.
Expect him to talk about ending the war in Iraq and promising to close the still-raging war in Afghanistan, particularly after mocking Romney for never addressing the latter in his own convention speech. Every speaker at the Democratic convention has contributed to the collective message that Obama wants to send of a diverse party that protects gay rights and women's reproductive rights.
Yet it all comes back to the economy, Obama's biggest burden.
"It's clear the president just hasn't lived up to his promises," Romney spokeswoman Andrea Saul said. "Jobs have declined, incomes have plummeted and household costs are skyrocketing."
Vice President Joe Biden, as forceful and colorful a defender of the president as they come, will have a chance to tell a different narrative when he takes the stage Thursday night.
And then the president will get his shot. Obama will speak in the 10 p.m. EDT hour.
The make-or-break election for the nation, as he likes to call it, is one for his political future as well.