Speaker Nancy Pelosi (D-Calif.) appears to be on a collision course with moderates over the long-term costs of the health care overhaul she is shepherding through the chamber.

Moderates are still trying to plot their strategy but are feeling a new sense of urgency to try to stop Pelosi from bringing a bill to the floor that fails to rein in health care spending and bloats the deficit. Those lawmakers want to act now to rework the bill rather than face a scramble after a tough review from budget scorekeepers.

“I don’t think our Members are aware that where the bill is now is not going to meet the tests of either of those, according to CBO, and they haven’t made any changes that would,— one senior Democratic aide said. “We’re getting toward the end and no changes are being made.—

Pelosi spokesman Nadeam Elshami said the fiscal concerns voiced by moderates were “shared by everybody in the Caucus.— He noted that leaders are still gathering input to form the final bill and haven’t set a deadline for shipping it to CBO. Pelosi herself on Wednesday described the package as “going around the bend— though not yet in the final stretch.

But House Democratic moderates see a bill coming together that lacks fundamental changes such as a tax on high-cost insurance plans or a tough Medicare cost-cutting panel. Without them, they fear Congressional Budget Office Director Douglas Elmendorf will restate his July assessment — that the House bill increases the long-term cost trajectory for health care rather than cuts it.

“The big picture is the president’s veto threat,— said Rep. Jim Cooper (D-Tenn.), a leading member of the fiscally conservative Blue Dog Coalition. “He said he would veto a bill that added a dime to the deficit in the short term or the long term. It would be embarrassing if we send him a bill that doesn’t do that.—

Those fears come as the Senate Finance Committee bill was preliminarily scored by CBO as actually cutting the deficit by $81 billion over the next decade with an $829 billion price tag, which had Senate Finance Chairman Max Baucus (D-Mont.) boasting.

Part of the problem in the House, moderates say, is that a tax on the wealthy that Pelosi has said “we’re pretty much committed to— doesn’t do anything to contain health care costs and won’t grow fast enough to keep up with rising medical costs long term.

“The bill I had to vote on in committee increased the deficit by $239 billion over 10 years, and it gets a lot worse in the second 10 years,— said Rep. Jason Altmire (D-Pa.), a leading member of the business-friendly New Democrat Coalition and a member of the Education and Labor Committee.

“Many of us are continuing to feel strongly that not enough is done on sustainability,— said Rep. Stephanie Herseth Sandlin (D-S.D.), a Blue Dog co-chairwoman. “If we’re going to extend benefits for coverage, we have to be able to sustain this over the long term. This is one of the primary reasons we’re undertaking health care reform.—

But while some moderates push behind the scenes for more austerity, few want to hold press conferences calling for cuts in Medicare, taxing insurance or less generous benefits. And while Blue Dogs have frequently urged more cost-cutting, they have not coalesced around a particular plan to do so. As liberals have noted, many in the group are rallying for a version of the public insurance option that would cost $85 billion more than the one liberal Members are pushing.

Pelosi is feeling the heat from a broad swath of her Caucus to stick to the original House bill with just a tweak or two. Some 157 Members signed onto a letter urging Pelosi not to change the bill to tax insurance plans, although they stopped short of threatening to vote against the bill.

Sophomore Rep. Joe Courtney (D-Conn.) led the letter-writing campaign, saying Wednesday that Democrats promised not to heap more taxes on the middle class and to reject taxes on health insurance during the campaign.

“We are sending the message to the other chamber and to the White House,— he said. “We are sending a big warning flag. … There is overwhelming opposition in the House.—

And a liberal bloc has frequently threatened to bring down the bill if a public insurance option is not included and based on Medicare rates, although moderates doubt whether they will actually vote against the bill.

A few changes that are being considered to get the CBO score down include increasing eligibility for Medicaid, which actually cuts costs because it is a public insurance option that pays low rates to providers.

Members are also looking at a compromise on the public option that would start it using negotiated rates and trigger Medicare rates if costs rise quickly. Another proposal would peg reimbursement rates for a public insurance plan 10 percent or 15 percent below private insurers rather than basing them on Medicare.

But some moderates say that while the short-term costs may come down, the CBO is still likely to slam the plan as failing to contain the deficit beyond the first 10 years.

Whether that’s really much of a political problem is open to debate. When Democrats pushed through a bill preventing a premium increase for wealthy seniors under Medicare recently, just five voted no.