Progressives in Congress are pushing for a last-chance reinstatement of the public option into health care reform during the reconciliation process between the House and Senate versions of the bill, but a group of centrist Democrats have declared they will accept few changes from the Senate version.

The House passed a version of health reform in November that includes a public alternative to private health insurers. The Senate bill passed Thursday has no public option. The two versions of health reform now face a reconciliation process.

The Hill reports that Sens. Mary Landrieu (D-LA), Blanche Lincoln (D-AR) and Ben Nelson (D-NE) -- three well-known centrist Democrats -- have told Senate Majority Leader Harry Reid (D-NV) that they expect few changes from the Senate version of the bill. The Hill reports:

They are the most vocal of nearly two-dozen senators who have indicated they see little wiggle room in the conference talks.

Centrists have said they will not vote for a healthcare reform bill that imposes a tax surcharge on the nation’s highest income earners or reduces the tax burden on so-called Cadillac health insurance plans, which are held by many unionized workers.

They have also threatened to vote against the bill if it includes a government-run health insurance program, a proposal that liberal Democrats in Congress acknowledge has little chance of winning inclusion in the final bill.

But in the reconciliation process congressional progressives see one last opportunity to resurrect the public option following its demise in the Senate version of the bill. Rep. Keith Ellison (D-MN) tweeted Thursday that the public option can still be saved "if we get loud now."

"Don't quit on [the public option]," Ellison tweeted. "Still very possible if we get loud now."

Evan McMorris-Santoro at TalkingPointsMemo reports that the Progressive Change Campaign Committee is pressuring left-leaning senators such as Russ Feingold (D-WI) to fight for the public option when it comes to conference early next year.

And David Sirota at the Huffington Post reminds readers that at least 6o Democratic House representatives have declared in writing that a health care bill without a public option "unacceptable."

Sirota notes that 60 House votes may be enough to at least force a serious debate on the public option.

It's right there in black and white - a bloc of legislators is saying that the Senate bill is "unacceptable." And not just any bloc, a bloc big enough to stop a final bill from passing into law. On a percentage basis, 60 House Democratic votes - or about a fourth of the Democratic majority in the House - is the equivalent of 15 Ben Nelsons in the Senate threatening to filibuster the final bill.