U.S. Senate Republicans are urging Democrats to oppose the sweeping health care reform bill that is facing a crucial vote on Saturday.

Senate Minority Leader Mitch McConnell and other Republicans told reporters Friday the health care bill would have a massive negative effect on a majority of Americans.  Fellow Republican Jon Kyl asserted that every opinion poll indicates strong opposition to the bill, and he called on Democrats to respect the wishes of their constituencies.

Saturday's procedural vote will determine whether the bill can be brought to the Senate floor for full debate.  It is not clear if Democrats have the 60 votes needed to do so.

On Friday, one moderate Democratic hold-out, Senator Ben Nelson, said he will vote yes in the procedural vote.

To avoid Republican maneuvers to delay the test vote, all 58 Democrats and two independent senators would have to favor the bill. 

Nelson said he will work to change parts of the bill that he opposes.  He said if that effort is unsuccessful, he will oppose the final bill.

Some moderate Democrats have signaled strong opposition to components of the bill, including a government-run option to compete with private insurers.  However, the Senate bill does allow states to opt out of the public option.

The Congressional Budget Office said the Senate bill unveiled Wednesday would cost $849 billion over the next decade.  Analysts say the plan also would reduce U.S. deficits by nearly $130 billion in the same period.

If the bill passes, it would have to be merged with a bill passed earlier this month by the House of Representatives.  The House narrowly approved its bill on a sharply divided vote of 220 to 215.

President Barack Obama has asked Congress to deliver legislation to him for signing by the end of the year.