Fox News contributor Dan Bongino said Monday that Sen. Bernie Sanders, I-Vt., is “unstoppable” on the path to win the Democratic nomination.

“It’s pure math at this point,” Bongino told “Fox & Friends," referring to the 1,991 delegates Sanders needs to clinch the nomination.

“Bernie right now is ahead in California, which has its prize of over 400 delegates. This is obviously a math equation at this point.”

TRUMP SAYS BUTTIGIEG'S EXIT A SIGN DEMS TRYING TO STOP BERNIE SANDERS

Moments after former South Bend, Ind., Mayor Pete Buttigieg told supporters he's ending his presidential campaign Sunday, President Trump said it reflected the growing pressure among more moderate Democrats to consolidate in order to blunt the rise of the more progressive Sanders.

Buttigieg previously had said Sanders was too liberal to be elected.

Buttigieg's withdrawal came just days before voters in 14 states are set to head to the polls on Super Tuesday, where one-third of all delegates for the nomination will be at stake.

Heading into key Super Tuesday contests, Sanders has led the overall race for delegates with 58 while Biden had 50. Sen. Elizabeth Warren, D-Mass., had 8 and Sen. Amy Klobuchar, D-Minn., had 7. It takes 1,991 delegates to win.

Bongino said that, historically, three lanes have emerged in presidential elections: An outsider lane, establishment lane, and radical lane.

He explained that Buttigieg is gone, dissolving the "outsider lane."

“When you look at the safe pick, the establishment lane, the vote is split. You’re going to have Bloomberg jump in the race on Super Tuesday and now you have Biden there.”

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“Bernie doesn’t have that issue with the vote splitting that Biden and Bloomberg do. He would’ve had it with Warren if she was putting on a formidable front, but she isn’t, so, again, it becomes simple fractions and simple math," he said.

“I don’t see anyone stopping Bernie,” Bongino said, pointing out that Bloomberg got into the race to stop Sanders but is now serving as the "spoiler" to Biden's chances.

Fox News' Frank Miles contributed to this report.