Senate Majority Leader Mitch McConnell on Tuesday changed a controversial provision in the rules for President Donald Trump's impeachment trial that would have required House prosecutors and White House attorneys to make 24 hours of legal arguments in just two days and could have barred evidence gathered by the House.

The last-minute changes — which were written by hand on the resolution, with other lines crossed out — were revealed Tuesday as the organizing resolution for the Senate trial was being read into the record on the Senate floor. The new version gives both sides 24 hours to make their cases over three days, instead of the two that McConnell, R-Ky., had proposed Monday.

Democrats complained that the two-day limit would have meant that they would be making their arguments until 1 a.m. or later, depriving much of the public from being able to watch the proceedings.

"If Leader McConnell is so confident the president did nothing wrong, why don't they want the case to be presented in broad daylight?" Senate Minority Leader Chuck Schumer, D-N.Y., asked Tuesday.

The change means the trial days, which start at 1 p.m. ET, will likely now end around 9 p.m.

It wasn't only Democrats who had issues with the timeline.

Sen. Susan Collins, R-Maine, "raised concerns" about the resolution and played a role in the changes, her spokeswoman said.

"Collins and others raised concerns about the 24 hours of opening statements in two days, and the admission of the House transcript is the record," Collins spokeswoman Annie Clark said in a statement. "Her position has been that the trial should follow the Clinton model as much as possible. She thinks these changes are a significant improvement."

Sen. Josh Hawley, R-Mo., who said he would vote to acquit the president, had also expressed displeasure with the resolution.

"I think that adhering to the Clinton model would have been my preference," Hawley told NBC News earlier Tuesday.

In President Bill Clinton's impeachment trial in 1999, both sides wound up presenting their cases over three days, with no limit on the number of days over which they spread their 24 hours.

McConnell also tweaked a controversial provision that could have barred all evidence gathered by the House Democrats' inquiry from being entered into the Senate record.

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Under the resolution read by the Senate clerk on Tuesday, the evidence now will be admitted automatically unless there's an objection, rather than be contingent on a proactive vote to admit it.

Schumer said the changes show that McConnell doesn't have an iron grip on the process, giving him hope that the Republican majority may bend on approving witnesses.

"Republican senators felt the heat and went to McConnell and said 'you've got to change it' shows that they can make other changes. And that we can get documents and witnesses," Schumer said. "In other words, this idea that Mitch McConnell, whatever he does every one of them will go along with, doesn't seem to be happening on two important issues."