Skirmishes between McCain, Democrats heat up

(CNN) -- Sen. John McCain, the presumptive GOP presidential nominee, and the Democratic candidates are trading shots almost daily in what may be preview of the general election.

McCain has targeted both Sens. Hillary Clinton and Barack Obama but has focused much of his fire on the latter after he emerged as the Democratic front-runner by winning 11 contests in a row.

McCain on Friday faulted the Democrats for wanting to renegotiate the North American Free Trade Agreement.

"I believe that those agreements should be kept,'' McCain said in Round Rock, Texas.

"And I believe that when someone -- as Sen. Obama and Sen. Clinton have said -- would renegotiate a treaty which went through years of negotiations with our leading trading partner Canada without consulting or without the agreement of our Canadian partners, I think it sends the wrong message to the world." Watch McCain call himself more qualified than Obama and Clinton »

Obama also has taken on McCain, even though his struggle with Clinton for the Democratic nomination is far from over.

"I honor and respect the service of John McCain. He is a genuine American hero and deserves our respect," Obama said Thursday while campaigning in Fort Worth, Texas.

"But John McCain, he embraces -- almost whole hog -- George Bush's policies."

Most of the exchanges between McCain and the Democrats -- especially Obama -- have been over Iraq.

"We are succeeding in Iraq when Sen. Clinton and Sen. Obama said the military 'surge' wasn't working. They were wrong," McCain said Thursday at a town hall meeting in San Antonio, Texas, referring to the increase of troops into Iraq that President Bush authorized last year.

"So I'm not asking them to apologize because they were wrong, I'm just asking them to join with us and support this strategy."

McCain pounced on Obama's remarks about Iraq in a Tuesday night debate with Clinton. Watch McCain, Obama battle over Iraq »

In the debate, Obama said, "If al Qaeda is forming a base in Iraq, then we will have to act in a way that secures the American homeland and our interests abroad."

Afterward, McCain said, "For Sen. Obama to say he would consider going back militarily if al Qaeda was in Iraq when Al Qaeda is in Iraq is probably one of the more remarkable statements that have been made on American national security policy." Watch as Iraq has re-emerged as a campaign issue »

Obama quickly shot back: "I have some news for John McCain. There was no such thing as al Qaeda in Iraq until George Bush and John McCain decided to invade Iraq."

Obama denies that he has shifted his focus to the general election despite the frequent exchanges with McCain.

"It's just that John McCain seems to be talking about me a lot, and obviously I want to make clear to voters in the Democratic primary that I am very confident about being able to make the case as to why John McCain is looking backward and we need to take this country forward," Obama said Thursday.

Obama and Clinton face key tests in Ohio and Texas on Tuesday. Clinton's supporters admit the former first lady must do well in these primaries if she is to continue to compete for her party's nomination. Watch how Texas' complicated caucus-primary system creates confusion »

Primary voters in Vermont and Rhode Island also head to the polls Tuesday.

Clinton has not engaged with McCain like Obama has. Instead she has focused on attacking her Democratic rival and presenting herself as the candidate with the experience to bring about the change that Democratic voters want.

"I really believe we need a president who on Day One who can be there to begin the change and regain our leadership and and respect .... We obviously need a commander in chief who will be able to get our troops out of Iraq but also make it clear we will protect and defend our interests in the world," she said during a rally Thursday in Hanging Rock, Ohio.

Clinton also worked to paint her rival as an untested commodity.

In an interview Thursday night on ABC's "Nightline," Clinton said Obama aptly described himself in his 2006 book.

"I think the best description actually is in Barack's own book, the last book he wrote, 'Audacity of Hope,' where he said that he's a blank screen," she said. "And people of widely differing views project what they want to believe onto him. And then he went on to say, 'I am bound to disappoint some, if not all of them.' "

Clinton's campaign said Thursday that she has raised $35 million in February, more than doubling the $15 million she raised in January.

The Obama camp hasn't released its campaign finance totals for February, but "we've raised considerably more than" Clinton's figure, Obama spokesman Bill Burton told The Associated Press.

The races in Texas and Ohio are competitive, polls suggest.

A "poll of polls" calculated by CNN for the Democratic contest in Texas has Obama at 48 percent and Clinton at 44 percent, with 8 percent unsure.

The Texas "poll of polls" is an average of five surveys -- Fox News/Opinion Dynamics, Belo/Public Strategies, American Research Group, Reuters/C-SPAN/Houston Chronicle/Zogby and CNN/Opinion Research Corp. -- conducted February 22 through Thursday.

A "poll of polls" calculated by CNN for the Ohio race shows Clinton ahead 47 percent to Obama's 40 percent, with 13 percent unsure.

The Ohio "poll of polls" is an average five surveys -- Fox News/Opinion Dynamics, Reuters/C-SPAN/Houston Chronicle/Zogby, American Research Group, University of Cincinnati "Ohio Poll" and Quinnipiac Poll -- conducted February 18 through Thursday. E-mail to a friend

CNN's Alexander Mooney contributed to this report.

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