U.S. Republican presidential candidate Marco Rubio speaks during a campaign event in Myrtle Beach, S.C., Feb. 11, 2016. 
Photo by Carlo Allegri/Reuters

Rubio faces scheduling struggles ahead of South Carolina primary

PAWLEY’S ISLAND, South Carolina — Marco Rubio’s been making the case to South Carolina’s voters that he’s the most conservative candidate in the race, but he missed one of his last opportunities to do so on Thursday night.

And technical difficulties with his plane further snarled his campaign plans Friday, just one day before voters go to the polls. Rubio was forced to reschedule a planned rally at an elementary school here, but the campaign has rescheduled the stop for 10 p.m. Friday night, a local GOP official told NBC News.

Nearly 900 people had RSVPed for the original event scheduled for 11:45 a.m.

RELATED: First Read: Is South Carolina getting closer?

On Thursday night, Rubio canceled a planned appearance at the Conservative Review conference in Greenville,  South Carolina, just minutes before he was scheduled to go on, organizers said. The event was running far behind schedule. Ben Carson, who was supposed to speak in the 7 p.m. hour, didn’t go on until around 8:40, long after Rubio’s scheduled appearance of 8 p.m.

Rubio’s campaign told reporters that the delay was behind the candidate’s decision, but gave no further explanation for his absence.

“Because of a delay in today’s schedule, Marco is unable to make the event below tonight. Senator Tim Scott and Congressman Trey Gowdy attended to represent the campaign,” Rubio spokeswoman Brooke Sammon said in a release.

Neither Gowdy nor Scott spoke on his behalf; organizers said they left the venue after it was clear Rubio had canceled his appearance, though the campaign speculated it was because organizers couldn’t find time for them to speak that night.

It was a missed opportunity to speak to a crowd of what organizers said was 5,000 conservatives, but it’s not clear it would’ve moved many votes for Rubio — the crowd was heavily tilted in Ted Cruz’s favor. Cruz signs blanketed the audience and he arrived on-stage, the second-to-last speaker, to a standing ovation.

Cruz, who’s been in a fierce and increasingly nasty fight with Rubio for votes in South Carolina as polls have shown Rubio narrowing his lead, made no mention of the Florida senator’s absence on-stage. But it didn’t go unnoticed — commentator Mark Levin, the keynote speaker of the night and a powerful voice in the conservative movement, mentioned it at the top of his speech.

“Marco Rubio, will you raise your hand?” He asked. “He was supposed to be here. Probably went to McDonald’s.”

This article first went to NBCNews.com

Marco Rubio and South Carolina

Rubio faces scheduling struggles ahead of South Carolina primary