Romney doesn't agree and says Obama's leadership has done little to jolt an economy hampered by an unemployment rate just over 8 percent.
"All the false and misleading ads in the world can't change one simple fact: Americans are not better off since President Obama took office," said Ryan Williams, a Romney campaign spokesman.
Obama's campaign spent about $6 million to buy airtime for the new ad in the key battleground states.
The fresh Obama push, coupled with ads this past week by both candidates squaring off over China's impact on the U.S. economy, comes seven weeks before Election Day and as polls point to modest gains for the president following the national political conventions. Both campaigns say they expect the race to be decided by eight or nine states.
Romney, a former business executive who argues that only he can fix the sluggish economy, was taking Saturday off from campaigning. He was trying to refocus his campaign on the economy after a difficult week dominated by foreign policy, a vulnerability, in the wake of unrest at U.S. embassies.
At the same time, Romney is working to reassure concerned conservatives that he has a winning strategy that relies partly on strong performances at next month's debates. He also was finalizing plans to make an aggressive push to try to narrow Obama's advantage among women and Hispanics.
The president was in Washington this weekend keeping tabs on the situation in the Middle East following the deaths of a U.S. ambassador and three other Americans. While he, too, had no plans to campaign this weekend, he also was keeping his eye on winning a second term.
The ad is an expensive and expansive effort by Obama to gain the upper hand on the economy, Romney's strength, at a time when voters are reporting feeling slightly more optimistic that the president's policies are helping.
Polls in several of the most contested states show the president with a slight edge. Also, a new national survey by The New York Times and CBS News finds that Romney has lost his long-standing edge on the question of who voters view as most likely to restore the economy and create jobs. Despite that, the poll found the race narrowly divided.
Obama's new ad features snippets from both presidents' convention speeches and serves as a rebuttal to Romney's argument that the nation is not better off than it was four years ago. It highlights news reports from September 2008 that describe the "worst financial collapse since the Great Depression" and says that, since then, the country has seen 30 months of private-sector job growth resulting in 4.6 million new jobs.
It argues that Obama would ask "millionaires to pay a little more" it doesn't mention that would come through a tax increase while Romney wants "a new $250,000 tax break for multimillionaires."
"We're not there yet, but the real question is, whose plan is better for you?" the ad asks.
Expect to hear the same argument next week as Obama holds rallies in Ohio on Monday, a fundraiser in New York on Tuesday and a two-city Florida swing on Thursday. The president is also expected to campaign next weekend in Wisconsin, the home state of GOP vice presidential nominee Paul Ryan and one that Romney is working to turn competitive.
Romney is set to campaign in Colorado on Sunday before Monday appearances in California and Texas. He'll spend Wednesday and Thursday campaigning in Florida.
Both candidates will appear separately at a forum this week hosted by the influential Hispanic television network Univision.
Romney aides acknowledge they're hoping for a shift away from foreign policy, which is not the longtime businessman's strength. While Romney tried to use the week's events to question Obama's global leadership, he drew criticism from Democrats and some Republicans for his initial response to violence in Libya.
For much of the week, the campaignlong struggle over the economy was shunted to the sidelines but not wholly suspended.
One day after Romney unveiled a television ad accusing Obama of "failing American workers" and ignoring unfair trade practices by China, the president's campaign responded in kind.
"He invested in firms that specialized in relocating jobs to low-wage countries like China," said the announcer in a commercial, referring to Bain Capital, the private equity firm Romney founded.
"Even today, part of Romney's fortune is invested in China," the narrator added. "Romney's never stood up to China. All he's ever done is send them our jobs."