Mitt Romney arrives in Colorado on Sunday to begin a critical, five-day run through states that will likely decide the outcome of the presidential race.
Romney will attend an evening rally at a Denver-area high school, hoping to bolster voter support in a state where polls show him losing ground to President Obama.
The GOP presidential candidate continues his swing-state run with a three-day bus tour in Ohio, followed by a stop in Virginia.
Obama won all three of those states in 2008, after Republicans won them four years earlier.
Romney is expected to provide more details about his economic plans for America -- amid criticism he has not been specific enough and that his campaign has veered off course.
The Sunday event ends a busy weekend of campaigning for both parties, with the first presidential debate one week away and Election Day about six weeks away.
GOP vice presidential candidate Paul Ryan made two stops Saturday in Florida, telling Cuban-American voters at a stop in Miami that he and Romney will restore the American Dream that brought them to this country
“People pick up and they go for a better life in this country,” Ryan said in the city’s Little Havana neighborhood. “Mitt Romney and I are trying to restore that.”
Obama made three campaign fundraising stops in Wisconsin. Vice President Joe Biden and wife Jill Biden made two stops in New Hampshire, including one with union members in Manchester. First lady Michelle Obama attended a Congressional Black Caucus event in Washington.
Romney has endured a rocky, past few days – including reports of internal campaign struggles and the surfacing of a secretly recorded video in which he says almost half of Americans don’t pay taxes and are dependent upon government.
Republicans on Sunday rallied around Romney, with Republican National Committee Chairman Reince Priebus saying the video surfacing was “not the best moment of the campaign,” but that the party still had a good week – in a “crystallizing” moment.
"We were able to frame up the debate last week in the sense of what future do we want and do you want out there for your kids and grandkids?" he said on ABC's "This Week."
Wisconsin Republican Gov. Scott Walker said on “Fox News Sunday” that he wanted to see “more passion” from Romney, like when he announced Rep. Paul Ryan as his running mate.
“I want to see fire in the belly,” Walker said.
In an interview set to air Sunday night, Romney told CBS' "60 Minutes" that his campaign is moving in the right direction. "It doesn't need a turnaround. We've got a campaign which is tied with an incumbent president to the United States," Romney said, according to remarks released in advance by CBS.
On Friday, Romney released his 2011 tax returns showing income of $13.7 million, largely from investment income. He spent much of this weekend raising money in California, a state Democratic presidential nominees have carried for nearly a quarter-century.
In Wisconsin, Obama attacked Romney's economic approach before a crowd of about 18,000 in Milwaukee.
"This country doesn't succeed when only a few do well," he said. "America succeeds when the middle class does well."
A recent Wall Street Journal/NBC/Marist poll showed Romney trailing Obama in Colorado and Wisconsin 45 percent to 50 percent.
Romney raised $6 million at the Saturday evening event that attracted celebrities Dennis Miller and Gary Sinise. Before a group of more than 1,000 California Republicans, Romney kept up his criticism of the president for fostering what he said was a culture of dependency.
"This is a tough time. These are our brothers and sisters. These are not statistics. These are people," Romney declared. "The president's policies – these big-government, big-tax monolithic policies – are not working."
Obama also looked to celebrities this weekend to help raise cash and keep bankrolling ads already saturating the most contested states.
Baseball great Hank Aaron supplied the star power at the Milwaukee fundraisers.
The president's campaign says Obama attended seven fundraisers and 14 public events since the day after the Democratic National Convention two weeks ago.
Over the past week alone, Romney has attended five public events, including three rallies, and more than a dozen fundraisers.
Romney adviser Kevin Madden defended the fundraising focus, while highlighting a shift toward swing states in the coming days
"We're here raising the resources we're going to need to compete in all those battleground states through Election Day," Madden said. "That's also been matched with a really intense battle ground state schedule that's going to be coming up starting Sunday night."
The Associated Press contributed to this report.