CHARLOTTE, N.C. – President Obama inherited a wreck of an economy, “put a floor under the crash” and laid the foundation for millions of good new jobs, former President Bill Clinton declared Wednesday night in a Democratic National Convention appeal aimed at millions of hard-pressed Americans yet to decide how to vote.

Conceding that many struggling in a slow-recovery economy don’t yet feel the change, Clinton said in a prime-time speech that circumstances are improving, “and if you’ll renew the president’s contract, you will feel it.”

To the cheers of thousands of Democrats packed into their convention hall, he said of Obama, “I want to nominate a man who is cool on the outside but who burns for America on the inside.”

Clinton spoke as Obama’s high command worked to control the political fallout from an embarrassing retreat on the party platform.

Under criticism from Republican challenger Mitt Romney, campaign managers abruptly rewrote the day-old document to insert a reference to God and to declare that Jerusalem “is and will remain the capital of Israel.” Some delegates objected loudly, but Los Angeles Mayor Antonio Villaraigosa, presiding in the largely empty hall, ruled them outvoted. White House aides said Obama had personally ordered the changes, but they did not disclose whether he had approved the earlier version.

The convention hall rocked with delegates’ applause and cheers as Clinton – unofficial Democratic ambassador-in-chief to anxious voters in a tough economy – strode onstage to sounds of “Don’t Stop,” his 1992 campaign theme song.

“In Tampa, the Republican argument against the president’s re-election was pretty simple: ‘We left him a total mess, he hasn’t finished cleaning it up yet, so fire him and put us back in,’ ” Clinton said.

“I like the argument for President Obama’s re-election a lot better. He inherited a deeply damaged economy, put a floor under the crash, began the long hard road to recovery and laid the foundation for a more modern, more well-balanced economy that will produce millions of good new jobs, vibrant new businesses, and lots of new wealth for the innovators.”

Obama flew into his convention city earlier in the day and arrived in the hall for Clinton’s speech. He arranged to join the former president onstage afterward in a made-for-television joint appearance.

Clinton shared prime time with Elizabeth Warren, the Democratic candidate for a Republican-held Senate seat in Romney’s Massachusetts. For many years, “our middle class has been chipped, squeezed and hammered,” she said.

In a tight race for the White House and with control of the Senate at stake, Democrats signaled unmistakable concern about the growing financial disadvantage they confront.

Officials said Chicago Mayor Rahm Emanuel, who was Obama’s first White House chief of staff, was resigning as national co-chair of the president’s campaign to help raise money for a super PAC that supports his re-election. Unlike candidates, outside groups can solicit donations of unlimited size from donors. At the same time, federal law bars coordination with the campaigns.

Inside the hall, a parade of speakers praised Obama and criticized the Republicans, sometimes harshly.

Sandra Fluke, a law student whom congressional Republicans would not let testify at a hearing on contraceptives, said if Republicans win in the fall, women will wake up to “an America in which access to birth control is controlled by people who will never use it, in which politicians redefine rape.“

Clinton’s speech marked the seventh consecutive convention he has spoken to party delegates, and the latest twist in a relationship with Obama that has veered from frosty to friendly. The two men clashed in 2008, when Obama outran Hillary Rodham Clinton’s wife for the Democratic presidential nomination.

Whatever the past differences between presidents current and past, Obama and his top aides looked to Clinton as the man best able to vouch for him when it comes to the economy, his largest impediment to re-election.