WASHINGTON — Two 2008 presidential aspirants used the confirmation hearing of Lieutenant General David Petraeus yesterday to carve out their positions on the war.

Senator McCain, a Republican of Arizona, used his time at the hearing to tack away from President Bush’s war plan, which he had supported. “Whether the projected surge is sufficient to accomplish all that our leaders will ask of our troops remains an open question in my mind,” he said.

Senator Clinton, a Democrat of New York, skated between the shades of anti-war sentiment in her party by promising not to defund the war but threatening to defund the Iraqi government. “I would never cut off funding for our soldiers in harm’s way,” she said. “But I would sure cut money for Iraqi troops. I don’t know how else to get their attention.”

The sparring at the Senate Armed Services Committee confirmation hearing yesterday underscores the dueling approaches to the war in the upcoming 2008 presidential contest.

Mr. McCain, who in early polls is running behind only Mayor Giuliani for the Republican nomination, has already been attacked in advertisements from the Democratic-affiliated group MoveOn.org for authoring the surge in American troops to Iraq. Yesterday the senator began to distance himself from that strategy, saying he had favored sending more troops than the president is proposing.

Mrs. Clinton also has been attacked from some members of her party for supporting the war. While she began to pivot this summer by calling for the resignation of the then-secretary of defense, Donald Rumsfeld, she now intends to add her name to a nonbinding resolution opposing any increase in troops. She also has proposed capping the number of soldiers in Iraq.

As General Petraeus, who is expected to become America’s next top commander in Iraq, asked lawmakers yesterday to bear with a strategy he does not expect to show progress until the summer, yet more mainstream Republicans were turning on the president’s surge strategy.

At the top of that list is Senator Warner, a former chairman of the Senate Armed Services Committee from Virginia. Mr. Warner announced yesterday that he will write his own nonbinding resolution with Senator Nelson, a Democrat of Florida, and Senator Snowe, a Republican of Maine, expressing doubts about the strategy to send more troops to Baghdad.

“We’re not a division here today of patriots who support the troops and those who are making statements and working on resolutions that could be translated as aiding and abetting the enemy,” Mr. Warner said. “We’re trying to exercise the fundamental responsibilities of our democracy.”

The prospect of a nonbinding resolution against the president’s proposed surge of 21,500 troops for Baghdad and Anbar province proved contentious at the hearing. At one point, Senator Levin of Michigan, the Democratic chairman of the committee, asked General Petraeus whether his remarks could be interpreted as endorsing or opposing any of the proposed resolutions.

General Petraeus said they could not. He did say later, however, when pressed by Senator Graham, a Republican of South Carolina, that he thought senators should consider any resolution a message sent to the troops and to America’s enemies.

In response to a question from Mr. McCain about what effect a congressional resolution would have on troop morale, the general said it would not be beneficial.

After the hearing, Mrs. Clinton told reporters: “Our troops are on the Internet constantly; they know very well there’s a debate going on in this country. … From the troops I’ve spoken with, a lot of them share many of the concerns that I and others have.”

Senator Lieberman, an Independent of Connecticut who caucuses with the Democrats, urged his colleagues to reconsider the nonbinding resolution. “I fear that a resolution of disapproval will send you over there with us saying you’re a good and great general but we don’t agree with what you believe we need to do in Iraq,” he said.

Mr. Graham was more blunt, daring his colleagues to cut off funding through the appropriations process if they really believe the war cannot be won. “If you think it is Vietnam today, if you really believe we’re in Vietnam, you should cut off funding,” he said.

In his testimony, General Petraeus described the coming phase in Iraq as a “test of wills,” warning that the enemy intends to “wait us out.” He came out in favor of the increase of troops, as well. “If we are to carry out the Multinational Force Iraq mission in accordance with the new strategy, the additional forces that have been directed to move to Iraq will be essential,” he said.

The general also warned that the “the situation in Iraq is dire. The way ahead will be very hard. … But hard is not hopeless.”