Moderate Senate Democrats voiced concerns about President Obama's budget Tuesday in a meeting with Budget Director Peter Orszag.

Sen. Evan Bayh, D-Ind., hosted the meeting, which was the second time moderate Democrats expressed concern over the budget.

 "I think there's a common concern about getting spending under control and making sure that there's a budget that doesn't have unsustainable requirements in it far into the future," said Sen Ben Nelson, D-Neb., who was one of twelve members at the meeting. 

Nelson has called the group the "Mod Squad."

Sen Joe Lieberman, D-Conn., who also attended the meeting, said the group is not expected to take a collective position on the budget, a move that could imperil the bill's prospects without some changes and also one that would give this group considerable clout. 

Still, Lieberman said he expects "some members of the group will vote for some amendments to curb spending," a top concern of the senator and his colleagues.

The budget is a blueprint, a nonbinding resolution that lays out targets for the year's annual spending and tax bills.

On the controversial idea of using a budgetary tool known as "reconciliation" to protect major new programs like climate change legislation and health care reform from a Senate filibuster, several members told FOX News they oppose the move, but again, don't expect a "Mod Squad" position.

Nelson called using reconciliation a "bad idea" and said he is prepared to vote against the budget if reconciliation comes back from House-Senate negotiations, as is expected for health care, specifically. 

The Senate budget currently has no reconciliation constraints, but the House budget does for health care. Critics of the move fear that health care reform will be paid for by using revenues from a massive new cap and trade program, which involves businesses buying and selling auction permits to pollute.

Sen. Mary Landrieu, D-La., also at the meeting, has said she is opposed to reconciliation and that she, too, is prepared to vote against the budget. Lieberman said only that he would "prefer" it not be included.

But Senate Majority Leader Harry Reid, D-Nev., again left the door open to using this risky tactic, when talking about both topics.

"How we pay for all this -- the budget resolution said we have to pay for it," he told reporters. "So we're going to have to pay for it. And I don't know how we're going to do that, but we're going to do it. We're going to pay for it."

Reid's own Finance Committee chairman, Max Baucus, D-Mont, who would write health care reform legislation, went even further Tuesday.

"We're going to work to get cost-savings from inside health care ... That's where we should first look," he said.

"To the degree that we need extra revenue, then we're going to look at extra revenue, see what makes the most sense," he added. "There's a whole variety of sources."

When asked specifically if he's leaving the door open to using cap and trade, "Oh yeah. The door's open, but as I've said constantly, everything is on the table. Everything is on the table. I'm not going to take anything off the table now. Then some member would want to know why his or her pet project isn't off the table."