House Democrats return to Capitol Hill today armed with a growing wish list for a final health care reform deal, despite repeated warnings from Senators that their wiggle room is limited.

[IMGCAP(1)]Democrats plan to hold a key caucus meeting tonight to talk about the upcoming negotiations with the Senate on a final bill. House leaders privately acknowledge that a public insurance option is dead, but they are nonetheless seeking a host of changes and tweaks to the final package that would collectively make it tougher on insurance companies and the rich and easier on the wallets of the middle class.

The House Democrats’ wish list includes beefing up affordability credits, nixing an insurers’ antitrust exemption and shrinking the “Cadillac— tax on high-cost insurance plans. And in return for agreeing to drop the public insurance option, House Democrats want a national insurance exchange instead of the patchwork of state-run exchanges called for in the Senate bill.

They also hope a voter backlash against Sens. Joe Lieberman (ID-Conn.) and Ben Nelson (D-Neb.) over concessions and special deals cut in the Senate version prompts the duo to show a modicum of flexibility.

But House Democrats also need their liberals to swallow their disappointment with the lack of their prized public option and rally behind a final bill. House Democrats have some wiggle room, but not much. The $1.2 trillion package cleared on a narrow 220-215 vote just before Thanksgiving. Senate Democrats corralled just enough votes to pass their version on Christmas Eve, persuading all 60 Members to come aboard.

Speaker Nancy Pelosi (D-Calif.) has sought repeatedly to reassure her flock that she won’t simply cave in to the Senate bill, including during a conference call last week in which she told Members that she is fighting for affordability for the middle class and accountability for insurers.

One House leadership aide said the White House, which has signaled support for the House’s affordability levels but also the Cadillac tax, holds significant leverage in improving the bill.

“It largely depends on how much support the White House gives us,— the House Democratic aide said. “They have an ability to push things one way or another.—

House Members also are peeved at Nelson’s carving out a Medicaid exemption for Nebraska. Nelson has said he would like to see all states have the same deal as Nebraska, but that would add billions to the final bill.

Pelosi also hopes to roll Rep. Bart Stupak (D-Mich.) and other anti-abortion Democrats who want to attach stricter language aimed at prohibiting women receiving federal health insurance subsidies from buying insurance covering the procedure.

One House aide said the public outcry against Lieberman and Nelson, and the prospect of getting to a final bill, should help House and Senate Democrats come together in the end. Senators don’t return to work until next week, but cross-the-Dome negotiations are expected to kick off in earnest this week.

“I think the dynamic of a final bill is different. … It has a positive impact,— a Democratic aide said.

A House Democratic leadership aide said that despite the pet issues that both chambers hold dear, the broad outlines of the bill are similar.

“If you look at the major provisions of the bill that are going to take effect, those are issues that Democrats have long supported,— the aide said. “Ending pre-existing conditions, closing the ‘doughnut’ hole, insuring 30-plus-million people — whatever form it’s going to take, these essential components are going to be in the bill.—

That’s a message that House Democrats will surely hear this week at their annual issues retreat, with Obama and former President Bill Clinton expected to rally the troops on the need to pass a health care overhaul.

David M. Drucker contributed to this report.