Why Nikki Haley’s presidential run helps Donald Trump

Former South Carolina governor Nikki Haley became the second major Republican to declare their 2024 candidacy on February 14.

When accounting for name recognition, Haley is probably the third choice contender in the party’s primary behind front-runners Donald Trump and Ron DeSantis. The market shares this perspective, with Haley given an 8% chance of winning next year’s nomination.

In my view, although Haley has little prospect of leading her party’s ticket in the presidential election, her presence in the race could still have significant effects.

The more Republican candidates there are, the better it is for Trump and the worse it is for DeSantis. In the last ten head-to-head polls in which respondents were only given a choice between the two front-runners, DeSantis came out on top seven times. However, when the same pollsters gave respondents an open choice of candidates, DeSantis led just once, with the poll margin moving in Trump’s favour by an average of 7.4 percentage points.

Broadly speaking, Republicans are divided into pro- and anti-Trump camps (those in the latter group don’t all dislike the former president, but would still vote for an alternative candidate if given the choice). Trump has already solidified a base of 40–45% of the party, so the more directions the remaining 55–60% is split in, the better it is for him. This is because Republican presidential primaries are not fully proportional, meaning the candidate with the most votes can win a majority of delegates even without a majority of the popular vote (as Trump did in 2016).

If the polls stay tight going into next year, the outcome of the Republican race could hinge on when (or indeed, whether) the minor candidates choose to drop out. If Haley is the best-placed outsider, she will cement her position as kingmaker with a potential vice-presidential pick undoubtedly used as her negotiating tool. Whether Trump convinces her to stay in or DeSantis gets her to drop out could end up deciding the outcome of this race.