Sign up for the Slatest to get the most insightful analysis, criticism, and advice out there, delivered to your inbox daily.

Exactly one month after Sen. Lindsey Graham’s death, GOP primary voters will head to the polls on Tuesday to vote for his replacement. It’ll be their second try this summer to pick a nominee—and it’s unlikely to be their last.

The party’s voters nominated Graham in June, shortly before his unexpected death in early July. In theory, the race to nominate his successor could end Tuesday, should one candidate win an outright majority. But with 10 contestants running, it’s more likely that the contest will narrow the field to a two-candidate runoff to be held Aug. 25.

The race is unlikely to affect the Senate’s balance of power next year: This is South Carolina, and even if the national environment favors Democrats come November, the GOP nominee is a heavy favorite to win Graham’s old seat. (Democrats have nominated Annie Andrews, a pediatrician from Charleston who lost a House race in 2022.)

But that doesn’t mean that the primary is without national importance: It represents not just a rare Senate opening in South Carolina (in the past hundred years, only four men have been elected to this seat) but a rare opportunity to discern the shape of the Republican primary electorate in a key 2028 primary state. It’s an opportunity to observe not only the continued power of Trump’s endorsement but also how much a particular flavor of MAGA-inclined Republican is popular among the party faithful.

Of the 10 contenders, four are considered to have a real shot at the nomination. Newly minted incumbent Darline Graham, the sister of Lindsey, was appointed to the seat initially as a placeholder. A political novice, Darline is a blank slate and has been notoriously press-shy since taking office. Although she did interviews with primetime Fox News hosts, she........

© Slate