Medical records clerk Elena Lara works in the medical records department at Clinica Sierra Vista's East Bakersfield Community Health Center in Bakersfield, California October 20, 2009. REUTERS/Phil McCarten

U.S. Senate Democratic leader Harry Reid released a long-awaited healthcare reform plan on Wednesday that budget analysts said would extend coverage to tens of millions of the uninsured and reduce the deficit over 10 years.

After weeks of closed-door talks to combine two Senate measures, the publication of Reid's 2,074-page bill quickly set off what promises to be a lengthy and bitter debate over President Barack Obama's top domestic priority.

Tonight begins the last leg of this journey, Reid told reporters after meeting privately with Senate Democrats.

The Senate bill includes a government-run insurance option that lets states choose whether to participate and would halt industry practices like denying coverage to individuals with pre-existing conditions.

Obama applauded the Senate legislation, calling it another critical milestone in the push for healthcare reform, but Republicans condemned it as a costly government intrusion into the private healthcare sector.

The bill's publication clears the way for a Senate vote as soon as this weekend on whether to begin debate -- the first key procedural hurdle for the Senate plan.

The nonpartisan Congressional Budget Office put the plan's 10-year cost at $849 billion -- below Obama's $900 billion goal.

The CBO analysis said the plan would reduce the deficit by $130 billion over 10 years, with small reductions in the second decade, and extend coverage to 31 million more Americans -- a rosy report card that could boost the bill's prospects in a sharply divided Senate.

The Senate bill is less expensive than a more than $1 trillion healthcare measure passed on November 7 in the House of Representatives. That bill would have covered at least 5 million more uninsured.

Republicans criticized tax increases in the bill to help pay for the expanded insurance coverage, including a new tax on elective cosmetic surgery they dubbed a Botox tax.

The bill would also raise the Medicare payroll tax on high-income workers, which is used to finance the government health program for the elderly, and impose a tax on high-cost Cadillac insurance plans.

Reid's version of the Cadillac tax is scaled back slightly from the version in the Senate Finance Committee that drew the ire of labor unions, a key Democratic constituency, which said it would harm middle-income workers.

'NOT A SHORT DEBATE'

This bill has been behind closed doors for weeks. Now, it's America's turn, and this will not be a short debate, Republican Senate leader Mitch McConnell said. Higher premiums, tax increases and Medicare cuts to pay for more government -- the American people know that is not reform.

If the Senate passes a bill, any differences with the House version would have to be reconciled before a final bill can be voted on again in both houses and sent to Obama to sign.

I look forward to working with the Senate and House to get a finished bill to my desk as soon as possible, Obama said in a statement.

The CBO analysis estimated that 3 million to 4 million people would enroll in a public insurance option, which would have slightly higher premiums than private insurers. Even with some states opting not to participate, it said about two-thirds of the population would have access to a public plan.

Like the House bill, the Senate measure would mandate that everyone buys insurance and set up exchanges where individuals could choose among various options. It also would offer subsidies to help the lowest-income Americans pay for coverage.

The bill does not include language approved earlier this month by the House that would strengthen the existing prohibition on using federal funds for abortion, senators said.

The healthcare overhaul has been stalled for weeks in the Senate as Reid waited for the CBO estimates and searched for a way to win the 60 votes needed to clear Republican procedural hurdles.

Reid did not say on Wednesday whether he had the 60 votes needed to begin the debate but Democrats have no margin for error. They control exactly the 60 seats in the 100-member Senate needed to overcome Republican opposition.

A handful of centrist Democrats have rebelled at Reid's decision to include a public insurance program in the bill but he has been working to corral their support.

When it comes time to vote, no one in our caucus is going to be the one or two who is going to sink this bill. It's just not going to happen, Democratic Senator Tom Harkin said.

Senator Ben Nelson, one of the uncommitted Democrats, said he would need to read the bill before making a final decision on whether to support the motion to open debate but added he was pleased with the steps taken so far by Reid.

Obama has made reform of the $2.5 trillion healthcare industry, which constitutes one-sixth of the U.S. economy, his top domestic priority and would like to sign a bill into law this year to try to keep it from becoming in embroiled next year's congressional elections.

If the Senate takes up the bill, the debate is expected to begin on November 30, after the U.S. Thanksgiving holiday next week, and last for at least three weeks.

Senior Democratic senators have said it is unlikely Obama will have a completed bill on his desk by the end of the year.