RENEE MONTAGNE, host: 

This is MORNING EDITION from NPR News. Bob Edwards is on vacation. I'm Renee Montagne. 

Congress gets back to work next week after a month-long break. While the lawmakers were away, budget analysts at the White House and on Capitol Hill said this year's surplus has vanished, except for the portion pledged to Social Security. Democrats say the culprit is a big tax cut President Bush signed in June. In a speech earlier this week, Mr. Bush made it clear he'd heard that criticism. President GEORGE W. BUSH: Now there are some who are second-guessing tax relief. You hear the voices beginning to filter out of their home states. I presume those who now oppose tax relief are for raising your taxes.

MONTAGNE: Some Democrats, in fact, do want to revisit the tax cut, but most seem reluctant to call for its repeal. NPR's David Welna reports from Washington. 

DAVID WELNA reporting: 

Democratic Senate Budget Committee Chair Kent Conrad was one of the most vocal opponents of the $1.3 trillion tax cut Congress approved last spring. He called it 'fiscally irresponsible.' Still, Conrad evaded questions this week about rolling back the tax cut. Instead, he insisted it's up to Mr. Bush and his fellow Republicans to resolve a shortfall in revenues that threatens to eat up some of the Social Security surplus. 

Senator KENT CONRAD (Democrat, Budget Committee Chairman): We're flying under their plan. They now have the responsibility to come back and suggest how their plan be altered to solve the problem they have created. 

WELNA: Other Democrats are equally blunt. California Congressman Robert Matsui says the tax cut is the problem, but the remedy, he says, won't come from Democrats. 

Representative ROBERT MATSUI (Democrat, California): It's our belief that because the president got the centerpiece of his economic program passed, which was the tax cut, now it's incumbent upon him how we're going to be able to get out of this fiscal mess we're in. 

WELNA: For Senator Evan Bayh, a moderate Indiana Democrat, the vanished surplus only underscores the need for the trigger mechanism he advocated earlier this year. He says his trigger would suspend the tax cut until there's enough money to pay for it. 

Senator EVAN BAYH (Democrat, Indiana): It's a matter of common sense to say, 'Look, we won't repeal the tax cut, but we'll make future phases of the tax cut, future additional tax cuts, contingent upon the money that makes them possible actually materializing.' 

WELNA: Democrats may be cautious about coming down too hard on a tax cut that some of their fellow party members voted for, and it's awkward to knock the cut while many tax rebate checks are still being mailed out. But former Labor Secretary Robert Reich says there's a more important reason why some of his fellow Democrats have shied away from the issue. 

Former Secretary ROBERT REICH (Labor Department): Democrats are absolutely petrified of being labeled taxers and spenders. Now it's one thing to be against a big tax cut, most of the benefits of which go to very wealthy people, but it's quite another to want to repeal a tax cut that's already been put into effect. That motion or movement to repeal looks an awful lot like a tax increase. 

WELNA: Still, there are some Democrats who seem ready to lead another charge against the tax cut, now that much of the surplus has vanished. Senator Paul Wellstone, a Minnesota Democrat who faces a tough re-election bid next year, told Minnesota Public Radio yesterday that it's time for Democrats to show some leadership in Congress. 

Senator PAUL WELLSTONE (Democrat, Minnesota): I think Democrats have every right and should say that this has all been irresponsible. It's exactly what many of us said would happen. But I think, in addition, we have to have the courage to say that you've got to make some changes. You have to challenge this tax cut. 

WELNA: The same kind of battle cry is being heard from some House Democrats. Jan Schakowsky of Illinois is gathering support for a bill to repeal the part of the tax cut that benefits the wealthiest taxpayers. She says it's an ideal time to revisit the tax cut. 

Representative JAN SCHAKOWSKY (Democrat, Illinois): We're saying that we're in a new circumstance right now, so that even people who supported the tax cut, we want them to take another look, as we should when circumstances in the country change, when the economy is going down. 

WELNA: But Democratic leaders in Congress, at least for the time being, are keen to avoid any action that looks like raising taxes. They prefer to let the president and his party try to find their own way out. 

David Welna, NPR News, Washington.