WASHINGTON (CNN) -- Democratic presidential front-runner Hillary Clinton said Sunday she won't vote for any more money to support the four-year-old war in Iraq without a plan to start bringing U.S. troops home.

Presidential hopeful Sen. Hillary Clinton greets people before speaking in Washington on September 17.

"I've reached the conclusion that the best way to support our troops is begin bringing them home," the New York senator and former first lady told CNN's "Late Edition with Wolf Blitzer."

"I don't believe we should continue to vote for funding that has an open-ended commitment, that has no pressure on the Iraqi government to make the tough political decisions they have to make, or which really gives any urgency to the Bush administration's diplomatic efforts."

Clinton's declaration comes as the Senate debates the Defense Department's 2008 spending authorization bill. It follows her vote against a $120 billion war-spending bill in May, when Congress dropped a call for the withdrawal of American combat troops by March 2008 after President Bush vetoed a bill containing that provision.

"The president has no intention of changing his policy in Iraq," she said. "He's now talking about leaving it to his successor."

Meanwhile, the Senate's Republican minority routinely filibusters Democratic proposals to wind down the war, which is costing the Treasury about $10 billion a month and has claimed the lives of nearly 3,800 American troops.

May's spending bill made continued U.S. support contingent on a set of benchmarks for Iraq's government.

But the Iraqis met only 11 of the 18 benchmarks, according to the Government Accountability Office, the investigative arm of Congress.

"Even those who are implementing this policy of the president's cannot tell us it will make America more safe, nor that it will lead to the kind of political decision-making that we have to expect from the Iraqis themselves," Clinton said.

Nearly two-thirds of the American public now opposes the war, according to a CNN-Opinion Research poll conducted in early September.

Clinton said, if elected president, she would end the conflict "as quickly and responsibly as I can," but said some U.S. forces would likely remain as trainers, to protect Americans and to battle Islamic militants loyal to al Qaeda.

The two-term senator, who leads her Democratic presidential rivals by a double-digit margin in national polls, made the rounds of all five Washington talk shows Sunday.

Last week, Clinton supported two amendments that would have forced the Pentagon to begin a U.S. withdrawal from Iraq.

But she said Sunday that even if Democrats muster enough Republican support to break a filibuster -- something they have been unable to do -- Democrats would still be unlikely to get the two-thirds vote needed to override a presidential veto.

"The answer for this is, let's elect more Democrats in 2008," she said. "That will help solve the problem." E-mail to a friend

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