Story highlights Romney campaigns in Colorado, gets more aggressive

Romney says more campaigning and less fundraising in the future

Obama ad ties '47%' comments to Romney's personal tax history

Polls in key swing states show Romney trailing Obama

Foreign policy drove the presidential campaign on Monday with Mitt Romney jabbing Barack Obama on overseas tensions ahead of the president's speech to the United Nations.

The Republican White House challenger used a campaign stop in the battleground state of Colorado to question Obama's handling of international affairs, considered a strength for the incumbent heading into the November election.

Romney keyed his attack around an interview aired on Sunday during which Obama said recent unrest in Libya would not prevent the country from developing a functioning government that adequately represents its people.

"I think it was absolutely the right thing for us to do to align ourselves with democracy, universal rights, a notion that people have to be able to participate in their own governance," Obama told CBS' "60 Minutes." "But I was pretty certain and continue to be pretty certain that there are going to be bumps in the road because, you know, in a lot of these places, the one organizing principle has been Islam."

Romney said Obama's comments belittled the gravity of the situation defined by the armed militant assault on the consulate in Benghazi that killed the U.S. ambassador and three other Americans two weeks ago.

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"These are not bumps in the road, these are human lives," Romney said in Pueblo. "These are developments we do not want to see."

Romney said the president's remarks were "surprising to people" given the unrest developing in a growing list of other international hotspots.

"Bumps in the road?" Romney asked. "We had an ambassador assassinated. We had a Muslim Brotherhood member elected to the presidency of Egypt. Twenty thousand people have been killed in Syria. We have tumult in Pakistan and, of course, Iran is that much closer to having the capacity to build a nuclear weapon."

Romney's comments were magnified by the White House decision not to schedule bilateral meetings between world leaders and Obama at this week's U.N. General Assembly, where the president will speak on Tuesday.

Obama's appointments in New York on Monday included a taping on the daytime talk show "The View."

House Majority Leader Eric Cantor told reporters in a conference call organized by the Romney campaign that the absence of any bilateral meetings at the United Nations, including with Israeli Prime Minister Benjamin Netanyahu, demonstrated an unwillingness to engage on issues that could become pitfalls for American diplomacy.

Netanyahu has called for a tougher U.S. response to Iran's nuclear ambitions.

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White House spokesman Jay Carney said on Monday that Obama regularly meets with foreign leaders, and that his duty as commander-in-chief "never ends."

"You are constantly engaged in matters of foreign affairs and national security. And that's what this president is doing," Carney said.

Taxes still on the table

While Romney shifted the focus to Obama's foreign policy, the Obama campaign took another whack at Romney on his tax returns and his controversial comments last week about half the U.S. electorate.

An Obama campaign ad on Monday said Romney "attacked 47% of Americans who pay no income tax, including veterans, the elderly and disabled."

This refers to a secretly recorded video in which Romney tells a fundraising audience last May that 47% of voters are dependent on government, see themselves as victims, and would vote for Obama "no matter what."

The ad then pivots to Romney's taxes, saying, "Mitt Romney paid just 14.1 percent in taxes last year" and claims that "he keeps millions in Bermuda and the Cayman islands."

Romney had been criticized by Democrats and some fellow Republicans for not releasing more than two years of tax records. He released his 2010 records in January and his 2011 returns on Friday, which included a summary of his taxes from 1990-2009.

The Romney campaign didn't address tax returns in response. It instead sought to contrast the candidate's tax policies with those of Obama.

Romney campaigned in Colorado following criticism from some Republicans that he was spending too much time fundraising. While Romney said he expects his fundraising calendar to be "a little quieter," a senior campaign adviser sounded less certain Monday.

"We're going to reach a point here, hopefully soon, where we'll have the resources we need to carry us through November 6 and we don't need to be doing those finance events," Ed Gillespie said on a call with reporters

Last month, Obama's campaign surprised political analysts by hauling in more money than Romney. Both campaigns are well on their way to record-breaking fundraising years. Counting super PAC dollars, it is likely that each campaign could break $1 billion.

Battleground polls seem to favor Obama

Two nonpartisan surveys conducted over the past two weeks indicate Obama has a five-point advantage, which is within their sampling errors, in Florida. Both the NBC News/Wall Street Journal/Marist and Fox News polls have the race at 49%-44%.

Other partisan surveys released since the end of the Democratic convention suggest a closer contest. Florida's 29 electoral votes are the biggest catch of the battleground states.

In Ohio, an NBC/WSJ/Marist poll and a Fox News survey each have the president holding a seven-point lead, while an American Research Group survey shows Obama with a two-point edge, well within that poll's sampling error.

Two nonpartisan surveys conducted over the past two weeks indicate Obama has a five-point advantage, which is within their sampling errors, in Florida. Both the NBC News/Wall Street Journal/Marist and Fox News polls have the race at 49%-44%.

Other, partisan surveys released since the end of the Democratic convention suggest a closer contest. Florida's 29 electoral votes are the biggest catch of the battleground states.

In Ohio, an NBC/WSJ/Marist poll and a Fox News survey each have the president holding a seven-point lead, while an American Research Group survey shows Obama with a two-point edge, well within that poll's sampling error.