WASHINGTON (AP) -- Republican John McCain and Democratic U.S. presidential rival Barack Obama were trading barbs as they began crisscrossing three Western states that are likely to be pivotal battlegrounds that could decide the November presidential election.
The two candidates recently have largely ignored Hillary Rodham Clinton, Obama's long-shot rival, who campaigned Monday in Puerto Rico. The U.S. Caribbean territory's primary on June 1 is one of just three left as the intense months-long battle for the Democratic presidential nomination winds down and Obama looks to be the inevitable nominee.
Obama was signaling, even before the Democratic primary campaign formally wraps up, that he intends to fight this fall for three Western states - New Mexico, Nevada and Colorado - that narrowly went Republican four years ago.
"We're going to fight as hard as we can in these states. We want to send the message now that we're going to go after them and I expect to win them," the Illinois senator said Monday in New Mexico.
McCain also spent the Memorial Day holiday in New Mexico where he used the occasion to criticize Obama for not having been to Iraq since 2006 and portray the first-term Democratic senator as naive on foreign policy and not experienced enough to lead the military.
Obama acknowledged that unlike McCain he has no military experience, but said he is committed to strengthening the military and improving veterans' services.
"As president of the United States, I will not let you down," he promised a group of veterans in New Mexico, a battleground state in the general election.
On Tuesday, Obama was heading to Nevada for campaign events in the Las Vegas area, where he was expected to focus on economic issues. In April, Nevada posted the worst foreclosure rate in the U.S., with one in every 146 households receiving a foreclosure-related notice, nearly four times the national rate.
Obama said he needs to introduce himself to Western voters. Issues like improving the economy, ending the Iraq war and providing universal health care will appeal to everyone, he said.
"I'm absolutely confident that we're going to do very well ... here because people out west are independent-minded and are going to look at whether or not over the last eight years the country is better off under Republican rule. I think they're going to conclude they're not and they want fundamental change, something that I'm offering and John McCain is not," he said.
McCain said Obama "has no experience, no knowledge or background" on Western issues.
"I believe as a Western senator I understand the issues, the challenges of the future for these ... states, whether it be land, water, Native American issues, preservation, environmental issues," McCain said in an interview with The Associated Press.
McCain was scheduled to speak in Denver on Tuesday before heading the following day for a town hall meeting in Reno, Nevada. Obama was heading to Colorado later in the week.
Together, the three states account for only 19 of the 270 electoral votes needed to win the White House. But those votes could be vital in a close race, particularly if Obama's weakness among white, working-class voters carries over from the primary race with Clinton and cuts his chance of winning some other states where Democrats usually do well.
U.S. President George W. Bush won New Mexico over John Kerry four years ago by the tiniest of margins - 49.84 percent to 49.05. His margins were not a whole lot bigger in Nevada (50.5 to 47.9) and Colorado (51.7 to 47).
The Obama campaign hopes that anger at Bush, combined with changing demographics as new voters move to the region, will nudge the states into the Democratic column.
On Memorial Day, the candidates highlighted their differences over the Iraq war. Polls indicate most Americans oppose the war, which has been overshadowed by economic concerns on the campaign trail, but could be a defining issue in the presidential election.
McCain, a Navy veteran and Vietnam prisoner of war, supports a continued military presence in Iraq though he recently said he envisions victory with most U.S. troops coming home by January 2013 if he is elected. Obama says he will remove U.S. combat troops within 16 months of taking office, though sometimes he shortens it to 11 months.
In the interview with AP, McCain noted that Obama's last trip to Iraq came before last year's military buildup that is credited with curbing violence, and said the Democrat's call for withdrawal is "inexcusable." McCain has been to Iraq eight times, most recently in March.
"He really has no experience or knowledge or judgment about the issue of Iraq and he has wanted to surrender for a long time," the Arizona senator said. "If there was any other issue before the American people, and you hadn't had anything to do with it in a couple of years, I think the American people would judge that very harshly."
Obama spokesman Bill Burton declined to respond directly to McCain.
"Senator Obama thinks Memorial Day is a day to honor our nation's veterans, not a day for political posturing," Burton said.
In his speech to veterans, McCain distanced himself from the Bush administration's handling of Iraq, acknowledging that Americans are unhappy with the war, but arguing that U.S. commanders in Iraq need more time.
"As we all know, the American people have grown sick and tired of the war in Iraq," the presumptive Republican nominee said. "I, too, have been made sick at heart by the many mistakes made by civilian and military commanders and the terrible price we have paid for them."
But, if the U.S. were to pull out now, "our defeat would be catastrophic, not just for Iraq, but for us."
McCain also defended his opposition to a Senate plan for increasing military veterans' college benefits, saying his was the right position rather than the politically expedient one, and suggesting Obama was on the wrong side of the measure sponsored by Democratic Sen. Jim Webb, himself a Vietnam veteran.
Obama spent much of last week criticizing McCain over the college aid bill, part of a strategy to link the conservative Republican - who favors staying the course in Iraq - to the deeply unpopular Bush administration.
The Democratic-controlled Senate approved the bill, which would substantially increase educational benefits for service members returning from Iraq and Afghanistan. Lawmakers blocked a more limited version that McCain supported. McCain opposed the Webb measure because it would give the same benefit to everyone regardless of how many times he or she has enlisted.
Obama said Bush is asking the troops to do too much with too little, such as interacting with civilians without the necessary translators and handling nation-building tasks that could be done by the State Department and other agencies.
Clinton, meanwhile, was in Puerto Rico, where she hopes for a big primary victory June 1. She met with a family whose soldier son is awaiting redeployment to Iraq, saying she would end the war so "you will not have to worry about him going back to Iraq." On Tuesday, she was heading to Montana, which along with South Dakota, hold the last primaries on the Democratic calendar June 3.
Clinton is trailing Obama and has almost no chances of getting the Democratic nomination. Some prominent Democrats have been calling for her to step down, fearing that a long nomination battle might ruin the party's chances in the general election.
The former first lady spoke of her determination to stay in the race despite trailing Obama, who has 1,977 delegates, just 49 delegates short of the 2,026 needed to clinch the nomination. Clinton has 1,779.
But only a total of 86 delegates are at stake in the last three remaining primaries.