Montana Republicans are demanding the state spend $750,000 it didn’t budget to avoid what the GOP sees as a potential political catastrophe: high voter turnout in an upcoming special election.

The state didn’t plan for spending on federal elections in 2017, and for good reason. Neither senator is running until 2018, and its lone House member, Ryan Zinke, seemed entrenched unless Senate Majority Leader Mitch McConnell taps him to challenge Democratic Sen. Jon Tester.

President Donald Trump, however, named Zinke interior secretary, setting the stage for a May 25 special election to fill the House seat. The race has received national attention, particularly from Democrats, who hope anti-Trump sentiment and increased Democratic Party activism since November’s election will boost their candidate Rob Quist to a surprise victory.

State lawmakers concluded that the special election would cost an unbudgeted $750,000, so they set about figuring a way to do it more cheaply.

A Republican lawmaker proposed a one-time mail ballot system. At the time, nobody in their right mind thought the election would be seriously contested ― Democrats haven’t won a House seat in Montana since 1994, after all ― and the state Senate approved the cost-saving measure.

But then something strange happened: The election got real. And Republicans who often boast of fiscal conservatism had a change of heart.

The GOP-controlled state House effectively killed the mail-in ballot bill on March 31, after the state GOP chair, state Rep. Jeff Essmann, wrote a letter to party members warning that a mail system would favor Democrats and hurt the GOP’s chances of holding onto the seat.

“Unless we have protections for ballot security in mail ballots, I think people should have the option to vote the way they want to,” Essmann told The Associated Press last month.

Democratic Gov. Steve Bullock revived debate over the matter on Friday, after he used his veto power to amend an unrelated piece of legislation to allow counties to conduct mail-in voting. Republicans, however, are seeking to delay those changes from being debated to prevent the bill from being brought to the floor, according to the Bozeman Daily Chronicle.

Bullock’s last-minute move to force a vote on mail-in balloting in the legislature may be too late, however. Election officials face a Monday deadline to present their plans to the secretary of state’s office, and some counties are already planning to print ballots and arrange polling sites.

Quist will face Republican Greg Gianforte in the May 25 special election.