Former UN Ambassador Nikki Haley vowed Tuesday to stay in the Republican primary beyond South Carolina, despite calls from some in her own party to suspend her underdog campaign.

Why it matters: Haley slammed GOP politicians who she says have "surrendered" to the "herd mentality" in politics, including many who "publicly embrace" former President Trump, but "privately dread him."

• "I'm not afraid to say the hard truths out loud. I feel no need to kiss the ring," Haley said during a speech Tuesday in Greenville, South Carolina.
• "I have no fear of Trump's retribution. I'm not looking for anything from him. My own political future is of zero concern."

Driving the news: Haley confronted the skeptics that she says are urging her to drop out of the GOP primary, while making her case against both Trump and President Biden.

• "We have two hugely flawed candidates in Biden and Trump, Americans know it," she said.
• "Trump and Biden are two old men who are only getting older."

Zoom in: Haley delivered a searing rebuke of the former president's legal trouble, saying it is a distraction from the campaign.

• "He's gotten more unstable and unhinged; he spends more time in courtrooms than he does on the campaign trail," Haley said.
• "He refuses to debate, he's completely distracted and everything is about him. He's so obsessed with his own demons from the past, he can't focus on delivering a future Americans deserve."

The big picture: Haley has repeatedly said that she is staying in the race until at least Super Tuesday, even as Trump holds a commanding lead and has swept the Iowa caucuses and New Hampshire primary.

• Haley brought in $16.5 million in January, which included $11.7 million from grassroots supporters.

What to watch: A strong performance for Haley in the Feb. 24 South Carolina primary is crucial to keep her campaign alive.

• Trump holds a strong lead in polling in Haley's home state and he's seeking a decisive victory there to all but wrap up the primary before Super Tuesday on March 5.
• The former president also has an endorsement edge over Haley in South Carolina, where he's won the backing of most top lawmakers.

Between the lines: Haley also grew emotional while speaking of her husband, Michael, who is deployed in Africa.

• "I wish our children and I could see him tonight, but we can't," she said. "He's serving on the other side of the world, where conflict is the norm."
• Trump earlier this month attacked Haley for the absence of her husband on the trail.

The bottom line: "I refuse to quit," Haley said.

• "South Carolina will vote on Saturday. But on Sunday, I'll still be running for president. I'm not going anywhere."

Editor's note: This story has been updated with new details.

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