I think you're both right, Nathaniel and Kaleigh, that there's no way Haley can win. She might just be staying in to prove a point and rally the non-Trump base to her side, to take a stand she can point to as prescient if Trump loses. But I think the big issue that she and most other Republicans have been dancing around is the four court cases around the country Trump is facing, his age and a range of any number of unexpected things that could happen between now and November. I think Haley might stay in the race in case something like a criminal conviction, a kind of deus ex machina for the primary that changes the story, without her having to really go after and fight Trump. The truth is he has a lot of potential weaknesses as a potential candidate, no matter how slim the potential for him to be actually sent to prison before November is. Maybe she's trying to position herself as the natural alternative should one of those things happen.

—Monica Potts, 538

Look, Haley is going to lose out to Trump for the Republican nomination. That's been apparent really before we even had votes to count, although it was right to see what actual voters would do in the early contests. But if Haley wants to risk what remains of her political career pushing back against Trump and what he means to the party she's dedicated her political life to, we shouldn't rule out that having longer-term practical implications and influence on voters. Acquiescing to Trump has been a pretty regular thing among Republicans since the 2016 election, but carrying a torch for an alternate vision is something Haley may be inclined to do, to hell with the consequences. Granted, the realities of continuing a campaign with less and less money coming in could end this race pretty soon, but we'll just have to see what she decides to do.

—Geoffrey Skelley, 538

To Jacob's point, the "go ahead and underestimate me" phrase is a very clearly gendered one. And Trump's reputation on this issue hasn't gotten as much attention as it did in 2016, but it's not clear that some of the issues have gone away. Plus, Haley may also be highlighting the fact that, as far as she is from being a real contender for the nomination, this is the closest any GOP woman has come.

—Julia Azari, 538 contributor

People forget this, but McMaster was the first statewide elected official to endorse Trump back in 2016. Haley’s appointment to U.N. ambassador cleared the way for him to become governor, a post he still holds today.

—Nathaniel Rakich, 538

Haley addressed supporters at about 8:30 p.m. Eastern, and vowed to stay in the race: "I said earlier this week that no matter what happens in South Carolina I would continue to run for president, and I’m a woman of my word," she said. Haley said she was frustrated and worried about the future of the country and the world, and that she was running to save it. "America will come apart if we make the wrong choices," she said. Again, Haley presented her case as one of electability. She said that we couldn't live with four more years of Biden's failures or Trump's lack of focus, and that the voters in future primaries deserved a choice, not a "Soviet-style election" with one candidate. With about 40 percent of the vote (as of now), she noted that it was roughly the same amount she'd gotten in New Hampshire. "I’m an accountant. I know 40 percent is not 50 percent," she said. "But I also know 40 percent is not some tiny group." Those people were looking for an alternative, and she said she shared their frustration. The electability argument is one that Republican primary voters aren't buying.

—Monica Potts, 538