Chris Wallace suggested that Mitch McConnell made a last-second change to the rules because he lacked support from Senate Republicans.

The Senate majority leader adjusted the impeachment trial rules to allow three days' worth of opening arguments rather than two just moments before the Senate trial began Tuesday afternoon. McConnell claimed the decision would prevent “dark-of-night” arguments from being made late in the day on Tuesday and Wednesday by allowing the discussion to continue into Thursday. He also changed a rule allowing all of the House's evidence to be admitted unless the full Senate votes to exclude part of the evidence.

This was the first time McConnell caved to the demands of Democrats in the impeachment trial, prompting Wallace to suggest that he didn’t have the Republican votes he needed to move forward with the rules as they were.

“Why did they make this change at the very last minute? Because clearly, there were four Republican senators, at least four, who were concerned about it who said, ‘Why do we have to rush? Why do we have to do this until 1:00 in the morning? It makes us look bad,’” Wallace said.

He added, "I think it’s fair to assume that the only reason that Mitch McConnell backed down, and he did back down, which is very rare for him, is because at least in his early procedural motion, there were at least four senators, four Republican senators, who said, 'Let’s soften this a little bit.'"

The Fox News Sunday host noted that the last-minute changes weren’t “that big a deal” and did not suggest that McConnell was going to struggle with future votes. He did, however, say that it likely means that some centrist Republican senators could be open to hearing from additional witnesses, such as John Bolton.

Wallace added, “Mitch McConnell is the majority leader, but if he doesn't have a majority, if the Democrats stand firm with 47 and then get four Republicans to jump over on a much more consequential issue like calling witnesses, if, then it's Chuck Schumer who is really the majority leader.”

One centrist Republican, Sen. Mitt Romney of Utah, said Tuesday that he didn't see the trial rules as controversial and urged Democrats not to feign outrage about differences between the trial rules for Trump and trial rules for President Bill Clinton, saying, "I think the Democrats make a mistake when they cry outrage time and time again. If everything is an outrage, then nothing is an outrage."