COLUMBIA, S.C. (AP) — President Donald Trump is not on the ballot, but he has invested time, energy and political capital in a slate of primary contests across America that will again test his clout within his own party.

Voters weigh in on candidates in seven states today, but the contest that matters most to Trump is South Carolina, where he appeared at a rally to help Gov. Henry McMaster hours before polls opened. The Republican governor, one of Trump’s first high-profile supporters, is fighting for his political life against self-made millionaire John Warren in a runoff election that threatens to embarrass the White House if McMaster falls short.

“Henry was for me from the beginning. There was nobody else,” Trump said Monday night before giving his audience an order: “Get your asses out tomorrow and vote.”

The South Carolina gubernatorial race headlined the latest in a series of primary contests that stretched across New York, Utah, Colorado, Oklahoma, Maryland and Mississippi today. With the November general election nearly four months away, more than half of all states will have selected their general-election candidates after the day’s votes are counted.

History suggests that Trump’s Republican Party, like the political party of virtually every first-term president dating back to Ronald Reagan in 1982, will face heavy losses this fall. Yet it remains unclear whether Democrats’ enthusiasm advantage demonstrated in the early months of Trump’s presidency will be enough to seize control of Congress and key governor’s offices nationwide.