US state primary elections produced mixed results for candidates backed by President Donald Trump, with businessman Mike Lindell suffering a defeat in Minnesota while his preferred candidate in South Carolina advanced to a runoff.The results showed the continuing influence, but also the limits, of Trump's endorsement as Republican voters selected candidates for key gubernatorial and Senate contests, reports said on August 12.In Minnesota, state House Speaker Lisa Demuth defeated Lindell in the Republican primary for governor. The MyPillow founder had received Trump's backing shortly before voting concluded, but the endorsement failed to propel him to victory in the three-way contest.Demuth also faced Kendall Qualls, an Army veteran and former healthcare executive. While Qualls had secured the Minnesota Republican Party's backing at its convention and Lindell had Trump's endorsement, Demuth relied on her record in the state legislature and experience in government to secure the nomination.Also read | Peggy Flanagan wins Minnesota Democratic Senate primary as progressives score another victoryDemuth will now take on Democratic candidate and US Senator Amy Klobuchar in the November election.Minnesota's Democratic primary for the US Senate also produced a clear result. Lieutenant Governor Peggy Flanagan won the nomination to contest the seat being vacated by Senator Tina Smith, defeating Representative Angie Craig.Flanagan, who is backed by progressive figures including Senators Bernie Sanders and Elizabeth Warren, had secured the state Democratic Party's endorsement earlier this year.Craig subsequently backed Flanagan, indicating that Democrats would enter the general election with the party largely united behind its nominee.In South Carolina, Trump's preferred candidate Darline Graham secured a place in the August 25 Republican runoff for the state's vacant US Senate seat. Representative Ralph Norman also advanced, setting up a two-way contest.Graham, who received Trump's endorsement, thanked the president for his support after making it through the primary. She also invoked her personal connection to the Senate race and spoke about her upbringing to underline her working-class background and political experience.Also read | Wisconsin governor's race: Progressive vs moderate battle of Democrats remains too close to callTrump reiterated his backing for Graham after the result, signalling that he intends to remain involved in the runoff campaign.The South Carolina contest will therefore offer another test of Trump's ability to translate his support into electoral victories.Meanwhile, Wisconsin's Democratic gubernatorial primary remained too close to call. Milwaukee County Executive David Crowley held a narrow lead of around 0.5 percentage point over state Assemblymember Francesca Hong, with about 87% of ballots counted.The contest pitted Crowley, a more moderate Democrat, against Hong, a democratic socialist. With a substantial number of votes still to be counted, Hong's campaign maintained that the race remained open.The Wisconsin result could therefore take longer to settle, while the outcomes in Minnesota and South Carolina have already provided contrasting signals about the strength of Trump's influence over Republican primary voters.The primaries are being closely watched as both parties prepare for November's general elections, with the results offering an early indication of the candidates and political themes likely to shape the upcoming campaigns.