Trump doesn't mention embattled GOP candidate Mark Robinson at North Carolina rally

Former President Donald Trump returned to the key battleground state of North Carolina for a rally Saturday, but declined to mention Mark Robinson -- his party's nominee for governor in the state.

The rally went on amid the allegations surrounding the Republican lieutenant governor, who the former president had previously supported and called "Martin Luther King on steroids."

Robinson, who did not appear at the rally, was accused of posting inflammatory comments on the message board of a pornography website more than a decade ago, according to a report published Thursday from CNN.

The embattled gubernatorial candidate had not been expected to attend Saturday's rally. Trump has not given any indication that he intends to pull his endorsement of Robinson.

In a statement Sunday, Robinson's campaign said four key staffers had "stepped down" from the campaign: general consultant and senior advisor Conrad Pogorzelski, III; campaign manager Chris Rodriguez; finance director Heather Whillier; and deputy campaign manager Jason Rizk.

"I appreciate the efforts of these team members who have made the difficult choice to step away from the campaign, and I wish them well in their future endeavors. I look forward to announcing new staff roles in the coming days," Robinson said in a statement.

Trump has campaigned for Robinson multiple times during this election cycle, including inviting him to speak at his rallies in North Carolina this year and hosting him at his Mar-a-Lago estate for a fundraiser last year.

People close to the former president told ABC News that they were bracing for the Robinson story on Thursday. The campaign was planning to put more distance between Trump and Robinson, but initially did not have plans to push him to drop out, sources said.

Robinson's beleaguered campaign, however, did come up at a rally headlined by vice presidential candidate Gov. Tim Walz in Allentown, Pennsylvania.

Walz insinuated that Trump was no "different" from Robinson.

"We got folks running as Republicans for governor that are proud to refer to themselves as Nazis. Let's not pretend that there's a gradual difference between the folks that are running here– that they're running together," Walz said.

ABC News' Isabella Murray and Katherine Faulders contributed to this report.