Texas Sen. Ted Cruz emerged victorious on Tuesday. The longtime Republican senator successfully drove off a near-upset by Democratic senatorial candidate Beto O’Rourke.

Cruz’s victory was by a narrow margin in traditionally deep-red Texas — 50.9 to 48.3 with 99 percent of precincts reporting.

A shocking undercover video released by conservative activists late Tuesday may explain why the contest was so unexpectedly close.

The footage, released by James O’Keefe’s political watchdog group Project Veritas, shows a young woman asking poll workers in Texas if it was okay for her illegal immigrant boyfriend to vote.

The unidentified worker replies that it’s no problem as long as he has an idea, and that “tons” of illegal aliens have been voting in her district.

“If he has his ID that’s all he needs, if he’s registered,” the worker says on camera.

“It doesn’t matter that he’s not a citizen?” asks the undercover journalist.

“No!” the worker insists. “No… If he’s registered, he has a… honey, it might not be that he’s registered? If he’s giving you all this trouble, it may be that he’s just not registered.”

The undercover video is reportedly from Travis County, Texas — a hotbed of Democratic support that voted 74.3 percent in favor of O’Rourke.

“He’s saying he saw something on the internet saying that it’s not legal for him to vote since he’s not a citizen,” the journalist says, repeatedly telling the poll worker that her boyfriend is a DACA “dreamer.”

“Don’t pay attention to that,” the poll worker assures the journalist. “Bring him up here.”

Speaking to another election judge at the same precinct, the journalist says her boyfriend is “nervous” and waiting in the car because he was an illegal immigrant.

“No, you tell him no, we got a lot of ’em,” the poll worker said. “Go get him, bring him in.”

You can watch the shocking video here —

Warning: This may upset some viewers.