(CNN) -- Sen. John McCain's campaign said Sunday that Barack Obama's remarks on Iraq "have left a significant question as to exactly what he intends."
Sen. John McCain's campaign says Barack Obama has not been consistent on Iraq.
"He has held almost every conceivable position in the course of his relatively brief career in the Senate," said Randy Scheunemann, McCain's foreign policy adviser.
Obama maintains his stance has not changed and said Saturday that "every single word" he says is closely measured.
McCain's campaign suggested Obama's views could be becoming more in line with McCain's Iraq policy.
"The position of [McCain's] campaign is that words do matter, and Sen. Obama's words have left a significant question as to exactly what he intends. If he is now joining Sen. McCain's position and saying that the need to maintain peace and stability in Iraq is a prerequisite before responsible withdrawal, which is Sen. McCain's position, we welcome his conversion to that position," Scheunemann said Sunday in a conference call with reporters.
The war over words started Thursday when Obama told reporters questioning his stance on Iraq that he will "continue to refine" his policies as warranted.
Obama denied any suggestion that he was shying away from his proposed 16-month phased withdrawal of all combat troops from Iraq, calling it "pure speculation" and adding that his "position has not changed."
National reporters and Republicans pounced on his comments. The Republican National Committee put out an e-mail statement saying that Obama was backing away from his position on withdrawal.
Speaking Sunday on CBS' "Face the Nation," Sen. John Kerry defended Obama and accused Republicans of avoiding "reality."
"The Republicans, and John McCain specifically, are trying desperately to get away from the reality of John McCain's position, which is that he has a plan for staying in Iraq and Barack Obama has a plan for getting out of Iraq... [Obama's position] is no change whatsoever in his fundamental determination to end the war," said Kerry, D-Massachusetts.
On the same program, Sen. Lindsey Graham of South Carolina suggested that Obama's stance would lead to failure.
"We're winning because John McCain understood Iraq better than anybody else. The surge has worked. The political, economic and military progress in Iraq is undeniable... The only way we can lose this war now is to go down the road that Obama suggests," he said.
Obama on Saturday said he was "puzzled by the frenzy" surrounding his words and maintained he's been "very consistent on Iraq." Watch: Obama clarifies his comments on Iraq »
Speaking to reporters Saturday as he flew from Butte, Montana, to St. Louis, Missouri, Obama said, "I was a little puzzled by the frenzy that I set off by what I thought was a pretty innocuous statement, which is that I am absolutely committed to ending the war."
Asked if he felt reporters made a mistake, Obama said, "I'm not trying to dump on your guys, but I'm surprised at how finely calibrated every single word was measured. I wasn't saying anything that I hadn't said before, that I didn't say a year ago, or when I was a U.S. senator. If you look at our position, it's been very consistent. The notion that we have to get out carefully has been a consistent position," he said.
Obama held a second news conference on Thursday to clarify his remarks.
Obama placed some of the blame for the confusion on the McCain campaign, saying "I think what's happened is that the McCain campaign primed the pump with the press to suggest that somehow we were changing our policy when we hadn't and that just hasn't been the case. I've given no indication of a change in policy ... I think John McCain's going to have a much harder time explaining how he is willing to perpetuate a presence in Iraq for 10, 20, 50 years."
Meanwhile, both candidates will turn their focus to key battleground states as they court voters across the country this week. Watch what's on the candidates' agenda »
Coming off a three-day swing through Colombia and Mexico, McCain is expected to tout his plan to create new jobs. He kicks off his week in Denver, Colorado, on Monday.
Both McCain and Obama will speak Tuesday at the League of United Latin American Citizens in Washington.
McCain has a town hall meeting scheduled in Portsmouth, Ohio, later this week, and Obama has events scheduled in Georgia and North Carolina -- two Republican-leaning states.
Obama is also expected to team up with former rival Hillary Clinton for three fundraisers in New York, according to an Obama spokeswoman.
Two of the fundraisers are aimed at raising money for Obama's Democratic presidential campaign, and one is to try to retire the debt from Clinton's failed effort to win the nomination.
On Thursday morning, they will appear together at a women's fundraising breakfast for Obama. All of the events are private.
CNN's Ed Hornick, Chris Welch and Steve Brusk contributed to this report.