Are you ready? Historic health care reform vote is today.

House Democrats are predicting that a rare Sunday session will produce one of the most significant legislative triumphs in decades: passage of a historic bill to overhaul the nation's health care system to provide coverage to millions of people who currently lack it.

Republicans resolutely opposed to the bill didn't concede defeat Saturday, but warned they will make Democrats pay dearly in the fall elections if the fiercely debated measure becomes law.

With President Barack Obama's emotional appeal from Saturday ringing in their ears, House Democratic leaders prepared for three showdown votes Sunday: on a "rule" to establish debate guidelines; on a package of changes to a Senate-passed bill, including deletion of special Medicaid benefits for Nebraska; and on the Senate bill itself, the focus of intense national debate for months.

Democrats need 216 votes to pass each one. With all 178 Republicans and at least two dozen Democrats vowing to vote no, the legislation's fate lies in the hands of about 20 Democrats who remained uncommitted late Saturday.

Party leaders appeared confident that most would break in favor of the bills. They pointed to Obama's emotional speech to the caucus at the Capitol, and they cited a sense of momentum from the handful of rank-and-file Democrats who have announced their support over the past several days.

Obama told House Democrats they have arrived at "one of those moments" when they can realize their highest aspirations in public life.

"This is one of those times where you can honestly say to yourself, 'Doggone it, this is exactly why I came here,'" he said. "'Because I believe so deeply in this country and I believe so deeply in this democracy and I'm willing to stand up even when it's hard.'"

If Democratic leaders prevail on all three House votes, Obama could sign the Senate version of the bill into law. The bill of "fixes" would go to the Senate under fast-track debate rules that would enable Democrats to pass it without facing a Republican filibuster.

Democrats control 59 of the Senate's 100 seats, one vote shy of the number needed to overcome bill-killing filibusters from a united GOP.

House Democrats have long insisted that senators agree to change the bill that the Senate passed on Christmas Eve. Since then, it became deeply unpopular with many Americans, because of the special deal for Nebraska, a new tax on generous employer-provided health plans and other aspects.

In a sign of increasing Democratic confidence Saturday, House leaders dropped plans for a controversial parliamentary tactic. They agreed to allow a simple yes-or-no vote on the Senate bill. By planning to pass the package of fixes on the same day, Democrats hope they can persuade constituents they did not support the Senate measure as a stand-alone bill.

The legislation, affecting virtually every American and more than a year in the making, would extend coverage to an estimated 32 million uninsured, bar insurers from denying coverage on the basis of existing medical conditions and cut federal deficits by an estimated $138 billion over a decade.

Congressional analysts estimate the cost of the two bills combined would be $940 billion over a decade.

House leaders continued to negotiate late Saturday with a handful of anti-abortion Democrats who threatened to switch from "yes" to "no" on the legislation without greater assurances that no federal money under the new laws would be used for elective abortions.

It was unclear whether Obama would agree to issue an executive order along those lines. Long-standing federal policy bars U.S. aid for abortions except in cases of rape, incest or when the mother's life is in danger.

House Speaker Nancy Pelosi and other top Democrats who joined Obama on Saturday spoke of the health legislation in historic terms, citing the many presidents who tried and failed to rewrite the nation's laws. Several cited tales of ordinary Americans struggling to pay bills when insurance companies denied or cut off coverage.

Republicans who vow to do all they can to stop the legislation in either congressional chamber "are not just delaying the inevitable, they are delaying the imperative," said Senate Majority Leader Harry Reid, D-Nev.

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