CLEVELAND, Ohio—Donald Trump supporters on Monday successfully pressured Republican delegates into rescinding their support for a measure that could have freed them to vote for an alternate presidential nominee.

Anti-Trump Republicans claimed that they gathered enough delegate signatures to force a recorded vote on convention rules, which require that delegates vote for the candidate that won their states’ primaries or caucuses.

When the measure came to the floor, Republican leaders declared that anti-Trump Republicans had fallen short of that threshold, quashing a last effort to “unbind” delegates from their obligation to back Trump.

According to Eric O’Keefe, president of a group of anti-Trump Republicans called Delegates Unbound, Trump allies in Cleveland approached delegates that backed the effort throughout Monday afternoon and pressured them to sign their names to documents rescinding their support.

Trump aides were seen berating delegates from states that backed the effort to force a recorded vote in the hours leading up to the floor fight.

If the rules had been voted down, the convention would have reverted to 2012’s rules package, according to O’Keefe, effectively permitting delegates to decline to back Trump.

Anti-Trump forces also could have pushed for new language freeing delegates from their commitments to Trump and allowing votes on alternate nominees.

O’Keefe said he had secured signatures from a majority of delegates from Colorado, Washington, Utah, Minnesota, Maine, Wyoming, Virginia, Iowa, and the District of Columbia demanding a recorded vote. Just seven states were needed to force the vote.

After a chaotic scene on the floor of the convention, Rep. Steve Womack (R., Ark.), who was overseeing the proceedings, declared that delegates from three states had withdrawn their support for the effort, putting those states below the majority threshold required to trigger a roll call vote.

It was not clear which three states had fallen below that threshold. Sen. Mike Lee (R., Utah), who led efforts on the convention floor for a recorded vote, called on the RNC to name the three states that had withdrawn from the effort.

“Something did just happen,” Lee said after the new rules package was ratified. “But the something that happened, we need an explanation.”

Delegates Unbound criticized Republican leaders in the minutes after the rules were enacted.

“Rigged election. Walk out,” the group told supporters as the scene unfolded. The Iowa and Colorado delegations did just that.

According to O’Keefe, the effort was about far more than Trump. The delegates behind the effort, which included veteran Republican operative Morton Blackwell and former Virginia Attorney General Ken Cuccinelli, were a “coalition against the centralization of power in these rules,” he said.

He predicted that Republican leaders and Trump allies would “just make up excuses” to sink the effort.