Brad Parscale claimed Wednesday night on Fox News' "The Ingraham Angle" that Mueller's news conference earlier in the day was an unfortunate development for House Speaker Nancy Pelosi, D-Calif., and candidates in her party running against Trump.
"The person who had a bad day today was Nancy Pelosi," Parscale told host Laura Ingraham. "The people who had bad days were the people running for president for the Democrats."
Parscale said Trump's potential opponents were "salivating" over the potential for damning information to come from Mueller's remarks.
He said he believed the prospect of a Trump impeachment is a key topic for Democrats heading into 2020.
"I still think this goes back to Democratic talking points," he said. "Impeachment to their base is like the wall is to our base. This is their fundraising thing. I think they were salivating something was going to come."
Parscale added he saw the Mueller report as a "made-up false problem" and border security as "a real crisis."
"This is about them raising money," he added.
The Kansas native claimed the Mueller probe helps Trump's reelection bid.
"It actually strengthens the campaign," he said.
Parscale also criticized U.S. Rep. Justin Amash, a Michigan Republican who claimed the president committed "impeachable" actions.
"He's not a libertarian," Parscale charged. "He believes in fake dossiers, he believes in spying."
Responding to a question from Ingraham, the campaign manager added he doesn't see Amash as a potential primary threat to Trump.