US president has been at the centre of this year’s midterm campaigns in a test of his influence.

Georgia Republicans have delivered mixed results for United States President Donald Trump in the state’s primary elections, opting for the president’s preferred US Senate candidate but rejecting his choice for governor.

Trump’s influence is being put to the test in this year’s midterm elections as four states and the District of Columbia held primaries on Tuesday.

In the Senate race, Republican Mike Collins, 58, topped former football coach Derek Dooley and advanced to face Senator Jon Ossoff, the only Senate Democrat running for re-election in a state that Trump won two years ago.

Ossoff, first elected during the 2020 cycle, has made Trump a focal point, blasting him as a “national embarrassment” who is using the presidency to enrich himself and his family.

Collins, a second-term congressman and a self-described “MAGA warrior”, echoes Trump’s false claims that his 2020 election loss in Georgia was rigged. Yet while celebrating his win, he thanked his wife, children, grandchildren, siblings, friends, supporters and staff but never the president.

The outcome of the midterm elections in November will determine control of Congress for the final two years of Trump’s second term.

In the race for Georgia governor, healthcare tycoon Rick Jackson, 71, outpaced Lieutenant Governor Burt Jones after spending about $100m of his own money on the campaign and surpassing Jones’s backing from the president.

Jackson will face Democratic nominee and former Atlanta Mayor Keisha Lance Bottoms in November.

The president was notably absent in Republicans’ remarks after the voting, a shift from other primary nights when candidates paid homage to their party’s leader despite his sagging approval ratings. Despite his endorsement for Jones, the president did not travel to Georgia to campaign with the candidate.

Jackson, a tremendously wealthy political newcomer, spent months comparing himself to Trump but didn’t do that as directly on Tuesday night. The president congratulated Jackson on social media, saying he “very successfully campaigned on being ‘TRUMP,’ and won”.

Trump’s mixed results in Georgia come after most of his preferred candidates have prevailed in primaries this spring.

The president will face another key test in Oklahoma in August when his pick for governor will face a Republican primary runoff.