WASHINGTON >> Senate Republicans will soon run out of time to rely on the barest of their majority to dismantle the Obama health law.

The Senate parliamentarian has determined that rules governing the effort will expire when the fiscal year ends Sept. 30, according to independent Sen. Bernie Sanders of Vermont, the ranking member of the Senate Budget Committee. The rules allow Republicans to dismantle the Obama health care law with just 51 votes, avoiding a filibuster.

“Today’s determination by the Senate parliamentarian is a major victory for the American people and everyone who fought against President Trump’s attempt to take away health care from up to 32 million people,” Sanders said in a statement. Sanders heads up Democrats on the budget panel and took the lead in the arcane arguments before the parliamentarian, who acts as the Senate’s nonpartisan referee.

Republicans control the Senate 52-48 and were using the special filibuster-proof process in the face of unified Democratic opposition. Now, if Republicans can’t revive the repeal measure in the next four weeks, they will be forced to work with Democrats to change it.

Senate Republicans pulled the plug on their Obamacare repeal effort in July, after falling short in a key vote. It has languished since, despite President Donald Trump’s call for senators to keep trying.

The ruling by Parliamentarian Elizabeth MacDonough is likely the final nail in the coffin, since it means Republicans would have to revive the effort and wrap it up in just a few weeks. Congress returns to Washington next week to face a packed agenda including Hurricane aid, a temporary government-wide funding bill, and raising the government’s borrowing cap to prevent a default on U.S. payments and obligations.

The bitter battle, and struggle among Republicans, over health care consumed the early months of Trump’s presidency. Now, the administration and its allies in Congress are eager to turn the focus to overhauling the tax code.