Sen. Bernie Sanders (I-Vt.) said Monday that everyone "should be aware" that former President Trump could announce an early victory, before races are called.

When asked in an interview by CNN's Kaitlan Collins what could happen if Trump declares a victory that isn't his, Sanders issued a warning.

"It's not 'what if.' Kaitlan, it is not 'what if' — he will," the senator said. "Everybody should be aware."

The Vermont independent claimed that as Election Day kicks off, Trump will announce early that he won "and the only way [they] could possibly lose is if there’s voter fraud."

"That is what will happen... this is why he has got to lose, because this is exactly how you undermine democracy: 'The only way I can lose is if there’s fraud.' Well, that means you can't lose a legitimate election," he added.

Last week, Trump started sowing doubt about the election results in Pennsylvania as he made explosive claims about fraud in the commonwealth.

“Pennsylvania is cheating, and getting caught, at large scale levels rarely seen before. REPORT CHEATING TO AUTHORITIES. Law Enforcement must act, NOW!” Trump posted last week on Truth Social.

A day earlier at a rally in Allentown, Pa., Trump highlighted reports about potentially fraudulent voter registration forms returned in Lancaster and York counties, though he misstated the nature of the issue.

“They’ve already started cheating in Lancaster. They’ve cheated," he said. "We caught them with 2,600 votes. No, we caught them cold."

Officials in Lancaster said they were reviewing about 2,500 voter registration forms due to possible fraud, though there were no fraudulent ballots involved and no indication that the forms are a sign of wider fraud, The Philadelphia Inquirer reported.

Claims of election fraud exploded in 2020 as Trump and his allies sought to portray their narrow election loss as something more nefarious. Concern that widespread fraud and misinformation could tilt the scale is on the rise again.

The fear comes as The Hill/Decision Desk HQ's polling index shows the former president and Vice President Harris tied with 48.4 percent support nationally.

The Hill has contacted the Trump campaign for comment.