With 60 votes in hand, Senate Democrats cruised on Sunday toward an expected victory on the first of three crucial test votes that will put a broad healthcare overhaul on the path to passage by Christmas.

Republicans said they did not have the votes to stop the bill but promised to keep fighting to delay passage and turn public opinion against President Barack Obama's top legislative priority.

The first test vote was scheduled for 1 a.m. EST on Monday in the snowbound nation's capital, with final Senate passage slated for the night of Christmas Eve as senators rush to finish before the end of the year.

What the American people ought to pray is that someone can't make the vote tonight, Republican Senator Tom Coburn said.

Democrats control 60 Senate votes, exactly the number needed to overcome Republican procedural hurdles. They secured the 60th vote for the bill on Saturday from the last holdout Democrat, Senator Ben Nelson.

The compromise with Nelson included language ensuring federal funds are not used to pay for abortions and securing extra healthcare funds for his home state of Nebraska.

The Nelson deal drew criticism from advocates on both sides of the abortion issue and from Republicans, who also admitted it would doom their quest to prevent it from passing before Christmas.

Asked if they could stop it, Republican Senator John McCain told Fox News Sunday: Probably not. But what we can do is continue winning the battle of American public opinion.

MORE WORK AHEAD

But if the health bill prevails in the Senate, it must be reconciled with a version passed in November by the House of Representatives that includes even stricter anti-abortion language and a government-run insurance option that was dropped from the Senate bill to appease moderates.

The merged bill will have to be passed again by each chamber before it is sent to Obama. Nelson said he will oppose the combined bill if it changes his abortion deal or reinstates the government-run insurance option.

The overhaul would spark the biggest changes in the $2.5 trillion U.S. healthcare system -- which represents one-sixth of the U.S. economy -- since the creation of the Medicare health program for the elderly in the 1960s.

The Senate bill would require most Americans to have insurance, extend coverage to 30 million uninsured Americans and provide subsidies to help some pay for it.

It would set up exchanges where those who are not covered by work-based policies could choose which plans to buy, and would halt industry practices like refusing insurance to people with pre-existing medical conditions.

Obama has asked the Senate to finish by the end of the year to prevent the issue from spilling into the campaign for November 2010 congressional elections. Opinion polls show the bill losing public support, with majorities now opposed to it.

The bitter fight over the healthcare plan has consumed the U.S. Congress for months and featured increasingly shrill rhetoric.

Democratic Senator Sheldon Whitehouse accused Republicans on Sunday of exercising malignant, vindictive passions in the debate and said they were embarked on a no holds barred mission of propaganda, obstruction and fear.

The vote early on Monday would formally cut off debate on an amendment offered on Saturday by Senate Democratic leader Harry Reid that made the final changes needed to win the support of all 60 Democrats.

In addition to the abortion compromise and the jettisoning of the government-run insurance option, the revisions required health insurance plans for large groups to spend at least 85 cents of every dollar on medical costs, potentially crimping their profits.

Democrats hope Republicans will surrender once Democrats prevail in the first few test votes. If Republicans hold out they can delay the vote until late on Christmas Eve.

(Editing by Sandra Maler)

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