By Richard Cowan

WASHINGTON (Reuters) - A draft opinion suggesting the U.S. Supreme Court was ready to overturn the 1973 Roe v. Wade decision establishing the right to abortion sparked a fresh call among progressive Democrats to scrap the Senate's filibuster rule.

"Congress must pass legislation that codifies Roe v. Wade as the law of the land in this country NOW. And if there aren’t 60 votes in the Senate to do it, and there are not, we must end the filibuster to pass it with 50 votes," Independent Senator Bernie Sanders said on Twitter.

Since the start of President Joe Biden's administration, Democrats have wrestled with repealing or modifying the long-held filibuster rule requiring at least 60 votes in the 100-member chamber to advance most legislation, as a way to get around their razor-thin majorities.

The move so far has been a political nonstarter and could backfire on Democrats as Republicans have a shot at winning majority control of the Senate in the Nov. 8 elections. Repealing the filibuster now could give Republicans a sure path to imposing new limits on abortion the next they control Congress and the White House.

Sanders was not alone in calling for an end to the filibuster, which Republicans have used to block major Biden initiatives, including his push for unprecedented government investments to rein-in climate change and provide new healthcare benefits to young families and the elderly.

"It’s high time we do it," chimed in Democratic Representative Alexandria Ocasio-Cortez on Twitter.

Sanders, Ocasio-Cortez and pro-choice politicians and organizations such as NARAL, face tough odds in loosening the grip of the Senate filibuster.

Last January, Democratic Senators Joe Manchin and Kyrsten Sinema joined forces with all 50 Republican senators against setting aside the filibuster so that voting rights reforms could pass the Senate.

On Tuesday, Manchin, who has opposed abortion rights, showed no sign of easing his opposition to a rules change to overcome the Supreme Court decision and legalize abortion through legislation.

"The filibuster is the only protection we have in a democracy" against a majority of senators steamrolling the minority, Manchin told reporters.

Last year, Sinema, a co-sponsor of legislation protecting abortion services, argued in a Washington Post opinion piece that filibusters foster "moderation." Neither she nor an aide were immediately available for comment on Tuesday.

But without Manchin and Sinema, Democrats see no pathway in the current Senate toward altering the filibuster and passing abortion legislation.

No. 2 Senate Democrat Dick Durbin, who is in charge of counting votes on controversial matters, said as much on Tuesday.

Asked by Reuters whether he saw any avenue for another attempt at changing the filibuster rule, Durbin said, "After I speak to two senators I'll tell you." He did not mention Manchin and Sinema by name.

(Reporting by Richard Cowan, Makini Brice, Moira Warburton, Jeff Mason and Gabriella Borter; editing by Scott Malone and Aurora Ellis)