Republicans negotiated behind closed doors long past midnight with skeptical senators to narrow some of the measures and rewrite parts of the bills. Mr. Cowles, who kept himself going with Diet Mountain Dew, had not seen enough changes to one of the bills to persuade him to support it. Not even a late visit to his Capitol office from Mr. Fitzgerald could make him budge.

Mr. Cowles’s opposition was not enough to derail the process. Mr. Vos huddled with Mr. Fitzgerald in the early hours of Wednesday. Finally, lawmakers returned to the Senate floor and shortly after sunrise, the most expansive cuts to Mr. Evers’s power had cleared both chambers.

Mr. Evers vowed to personally lobby Mr. Walker to veto the measures. If that failed, he said litigation was on the table. Mr. Walker did not respond to an interview request.

“We will not just lie down and accept this,” Mr. Evers said. “We believe it was the wrong step and we’re going to continue to take the steps necessary to change that.”

An Eight-Year Pattern

For Wisconsin Republicans, pressing forward with speedy changes over loud opposition was nothing new. In 2011, they cut benefits and collective bargaining rights for most public-sector workers as thousands of protesters chanted in the Capitol and as Senate Democrats fled the state to try to slow the measure. In 2015, they pushed through a right-to-work bill over the furious chants of labor union members after late-night meetings.

“They have this way of thinking from those experiences — if we can just gut this out and deal with the protest and have a day of pain, we can ram it through and just be done,” said Charlie Sykes, a conservative former radio host in Wisconsin who has been critical of Republicans lately. “But those earlier ones were about something meaningful. I don’t think they understand the optics of this. It creates the image of a last-minute power grab.”

But Mr. Fitzgerald said he believed that many Wisconsin voters will support what Republicans did. “There’s a reason that the Legislature is Republican in both houses, and I think people are going to be comfortable with this divided government once they see how liberal Tony Evers is,” Mr. Fitzgerald said.

“You cannot argue that the state has ever been in a better position than what we are right now,” he said. “It’s just one thing after another that makes Wisconsin look awesome.”