Updated

Without casting a single vote yet on health care legislation, the Senate already has reached something of a stalemate over amendments.

After three days of debate, Senate Majority Leader Harry Reid called a closed-door meeting to rally Democrats.

Democrats contend that Republicans are obstructing, as they have insisted on three days of debate on an amendment from Sen. John McCain that blocks nearly $500 billion in Medicare cuts Democrats have made to help pay for health care reform.

Republicans counter that they are not obstructing because Reid can move to "table," or kill, the McCain amendment at any time, a move that would require only 51 votes.

There's also the government-run insurance option that Republicans strongly oppose and Democrats are divided on. Several moderate Democrats oppose it so Delaware Democrat Tom Carper is seeking an alternative -- but no amendment is ready.

Another issue is abortion. Sen. Ben Nelson, a moderate Democrat from Nebraska, is working on an amendment to prevent tax dollars from funding abortion with language similar to what passed the House last month. But he doesn't have the votes yet.

The first pair of amendments was supposed to be cut and dried: there is ample bipartisan support for Sen. Barbara Miklulski's amendment expanding women's health screening. They just haven't voted yet because they can't decide what to do next."

A spokesman for Senate Minority Leader Mitch McConnell said, "We're not going to insist on three days for every amendment. Some will take a short amount of time, others longer."

Democrats are now threatening to work through Christmas with a goal of passage by the end of the year. They are expected to table McCain's amendment, rejecting the GOP's first proposed amendment for a health care debate that has gotten off to rough start.

Fox News' Carl Cameron and Trish Turner contributed to this report.