U.S. Senate Democrats are in last-minute internal talks ahead of a crucial vote on the Clarity Act, a cryptocurrency market-structure bill.

On Sept. 13, blockchain media outlet U.Today reported that Senate Democratic leader Chuck Schumer will convene a Democratic caucus meeting on the evening of Sept. 14 to discuss issues ahead of a procedural vote scheduled for Sept. 15.

The vote is seen as a watershed that will determine whether the bill can move to the full Senate consideration stage. If the procedural vote passes, the bill can proceed to broader review on the Senate floor. If it fails, discussions on comprehensive cryptocurrency market-structure legislation are more likely to be delayed again.

In the Senate, about 12 Democratic senators have negotiated over the bill for months, but key issues remain unresolved. The biggest obstacle is a stronger conflict-of-interest restriction that Democrats are demanding. Democrats want to strengthen the provision, but a final agreement has not been reached.

Participants are reported to include Senators Kirsten Gillibrand, Mark Warner, Ruben Gallego, Lisa Blunt Rochester, Andy Kim and Angela Alsobrooks. They are continuing to coordinate on how to amend the bill and how to secure support within the party.

The vote threshold is also a variable. The bill needs 60 votes to move to the next step. Even assuming all Republican votes line up in favor, it would still need at least a few Democrats to join to clear the procedural vote. That is why some see the outcome as uncertain.

The bill already passed the Senate Banking Committee in May in a bipartisan vote. The committee advanced the bill by 15 votes to 9. The Senate then released a new revised version of about 630 pages on Sept. 11. With little time left, discussions earlier this week are likely to influence the direction of the vote.

Markets are also watching the weekend negotiations. Galaxy Digital CEO Mike Novogratz said on Sept. 14 that negotiations have continued throughout the weekend. Senate leadership is also seeking a last-minute compromise to narrow differences before the vote.

A warning has also been issued about delays. Senator Cynthia Lummis previously warned that if the bill cannot move forward, comprehensive cryptocurrency market-structure legislation could be delayed by years. In that context, the Sept. 15 procedural vote has emerged as a test of whether the U.S. Senate’s debate on institutionalising cryptocurrency will gain speed, beyond being a simple preliminary step.