The U.S. Senate will hold its first crucial vote on a sweeping health care reform bill this Saturday.

Senate Majority Leader Harry Reid announced the test vote Thursday, a day after he unveiled the Senate's health care bill that aims to extend health insurance to 31 million more Americans. 

Saturday's procedural vote will decide whether the bill can be brought to the Senate floor for full debate, although Reid would not comment on whether he had the 60 votes needed to do so.

To avoid Republican maneuvers to delay a vote, all 58 Democrats and the two Independent Senators have to favor the bill.  A few moderate Democrats have signaled strong opposition to components of the bill, which includes a government-run option to compete with private insurers.

However, the Senate bill does allow states to opt out of providing a government-run option. 

The Congressional Budget Office said the Senate bill unveiled Wednesday night would cost a total of $849 billion over the next decade.  Analysts say the plan would also reduce U.S. deficits by nearly $130 billion in the same period, a report that could boost  the bill's chances of passage.

If the bill passes, it will have to be merged with a much larger 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.

(Some information for this report provided by Reuters and AP)