WASHINGTON (The New York Times News Service) -- Senate Majority Leader Harry Reid, D-Nev., said Tuesday that his chamber would "not be bound by any timelines," potentially pushing President Obama's top domestic priority into next year.

The calendar is closing in rapidly on lawmakers. Before legislation reaches Obama's desk, it must pass both chambers of Congress twice.

First, the House and Senate each must pass their individual bills; then House and Senate negotiators must reconcile the two versions that are likely to conflict on such basic elements as which taxes to raise to pay for expanded coverage.

And then each chamber must vote on final passage of a melded bill.

Reid has promised a wide-open Senate debate with lots of amendments, a strategy considered essential for legislation as complex and controversial as a remake of the U.S. health care system.

But that kind of debate can easily consume several weeks. Reid still has not locked down the 60 Democratic votes he needs even to begin that process.

Reid downplayed his difficulties Tuesday, blaming the delay on the Congressional Budget Office, which first must analyze the cost of a bill he submitted to the agency a week ago. Democrats said CBO is not expected to issue its report this week, and Republicans said Reid submitted a "concept" rather than a bill.

But a bigger problem is Reid's own Democrats, mainly a handful of moderates who may not vote for a bill that contains the public option -- government-sponsored insurance coverage -- that liberals favor.

Sen. Charles Schumer, D-N.Y., said he was "still hoping" to finish the legislation by Christmas, but conceded that things are going "slower than we thought . . .The most important thing to do is to get it right."

Each day that goes by puts the Thanksgiving deadline further out of reach, and endangers what was once considered a drop-dead date near Christmas.

Pushing the legislation to January was long considered unthinkable by most Democrats, who for months have insisted that they must pass health care before the inertia of next-year's mid-term elections sets in.

A long Christmas break could stall the momentum that leaders have tried time and again to muster, including at an event that House Speaker Nancy Pelosi, D-Calif., held just last week on the Capitol steps to showcase the House legislation.

Republican victories in Tuesday's gubernatorial races in Virginia and New Jersey could further frighten Democratic lawmakers from swing districts, although Democrat maintained that health care has not been a major issue in either of those campaigns.

Pelosi is still trying to resolve differences among Democrats in her own chamber, where questions over how to prevent federal funds from paying for abortions continue to delay action.

House rules and a bigger majority give Pelosi a major advantage over Reid, who labors under Senate rules that allow any single member to block legislation. A House vote could take place later this week.

Sen. Barbara Boxer, D-Calif., who was battling her own GOP boycott of climate change legislation in the Environment and Public Works Committee, expressed optimism that health care legislation would be enacted. She said small business people were "beside themselves" over the rising cost of health care and its effect on jobs.

Boxer called her decision to join the move of Sen. Ron Wyden, D-Ore., to open the planned health insurance exchanges to those who have insurance through their employers a "no brainer."

Under House and Senate bills, the planned exchanges would offer a range of choices to a limited number of people who either cannot get insurance now or work for small businesses.

Experts believe such small exchanges would not provide enough competition to restrain cost increases in the employer-based plans that most people use.

"I think Ron is right," Boxer said. "It's really important that there be a great deal of choice for all of our people.

"The broader array of choices people have, the more competition there will be. If you have a robust exchange, you really bring down the costs to the individual, to small businesses, to the uninsured, to everybody."

Copyright 2009 The New York Times News Service. All rights reserved.