WATCH: GOP's Nancy Mace begs for support outside Trump Tower after Trump backs her challenger

A Republican lawmaker posed outside Trump Tower in New York City to pledge her loyalty to the former president after he endorsed her primary challenger.

Rep. Nancy Mace (R-SC) posted a video of herself standing outside Donald Trump's high-rise residential tower in Manhattan one day after the ex-president endorsed her GOP challenger Katie Arrington, who scored the endorsement a day after announcing her candidacy in a four-way Republican primary, reported The State.

“If you want to lose this seat once again in a midterm election cycle to Democrats," Mace said in the video, "then my opponent is more than qualified to do just that."

Trump attacked Mace as "disloyal" and "terrible" in his statement endorsing Arrington, but the lawmaker claimed to be one of his earliest supporters and touted her work on his campaign in 2016.

“As a strong fiscal conservative, I believe in putting America first," Mace said in the video. "I believe in putting our country back on the path to prosperity. But Nancy Pelosi would love nothing more than to win the seat back in the midterm election cycle. She did it ‘18 And she could do it again this cycle."

Arrington responded with mockery and derision.

“Nancy- did you get lost on your way to the Fox News Studio? Or are you in NYC to fundraise with the progressives?” Arrington tweeted. “What does NYC have to do with the Lowcountry?”

Mace apparently angered Trump by blaming him for the Jan. 6 attack that "put all of our lives at risk."

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