The cut and run Democrats are really living up to their name and I think they are going to live to regret their strenuous and obstinate objection to winning this war in Iraq:

Senior House Democrats said yesterday that they will attempt to derail funding for President Bush’s proposal to send an additional 21,500 troops to Iraq, setting up what could become the most significant confrontation between the White House and Congress over military policy since the Vietnam War.
Senate Democrats at the same time will seek bipartisan support for a nonbinding resolution opposing the president’s plan, possibly as early as next week, in what some party officials see as the first step in a strategy aimed at isolating Bush politically and forcing the beginning of a phased withdrawal of U.S. troops from the conflict.
The bold plans reflect the Democrats’ belief that the public has abandoned Bush on the war and that the American people will have little patience for an escalation of the U.S. military presence in Iraq. But the moves carry clear risks for a party that suffered politically for pushing to end an unpopular war in Vietnam three decades ago, and Democratic leaders hope to avoid a similar fate over the conflict in Iraq.
[…]
Those plans could attach so many conditions and benchmarks to the funds that it would be all but impossible to spend the money without running afoul of the Congress. “Twenty-one thousand five hundred troops ought to have 21,500 strings attached to them,” said House Majority Whip James E. Clyburn (D-S.C.).
Brendan Daly, a spokesman for Pelosi, said Democratic leaders have made no decision to hold back funds, but he added: “We are not going to give the president a blank check. We will subject any proposal to escalate the war to harsh scrutiny, and we will set benchmarks he has to attain to get that money.”
[…]
House Democratic leaders have said they will not use the power of the purse in any way that would harm troops in the field, a position that had run afoul of the party’s liberal activists. Rep. Ellen O. Tauscher (D-Calif.), a member of the Armed Services Committee, said that pledge is being calibrated to apply only to troops in the field now.

(via)
By the time they pass the bill the surge will have already started and they will be denying funding for troops already over there:

A first wave of additional U.S. troops will go into Iraq before the end of the month under President Bush’s new war plan, a senior defense official said Tuesday. Congressional Democrats kept up their criticism of plans to add soldiers in the unpopular conflict.

The Democrats are attempting to defund the troops because their base is pushing them to do it:

Antiwar activists continued to press congressional Democrats to block Bush’s plans. “The bottom line is that when voters elected the Democrats, they did that on the promise that the Democrats would lead the country out of the war,” said Eli Pariser, director of the MoveOn political action committee. “Democrats need to fulfill on that promise, and they’re going to.”

Looks like this is going to get really messy. Bush is sending the troops, they are already being deployed and the Democrats are going to be pushed into acting. It will be interesting to see what they will do, especially given the fact that there are some Democrats that actually support the war.
Updated to add: I wish a reporter would ask them how they can say they will support the troops that are already there but not the new ones when the new ones will be there by the time they pass a bill:

“We are going to fund the troops that are there,” said Brendan Daly, an aide to Representative Nancy Pelosi of California, the House speaker. “Any escalation of troops we will subject to scrutiny. We will have hearings, and we will set benchmarks that the president must meet to obtain this money.”
Any challenge to Mr. Bush over paying for the additional troops is probably months away. House Democrats said their first step would be to vote on a nonbinding resolution opposing Mr. Bush’s plan. The Senate is planning to vote on a similar resolution as soon as next week.