President Trump’s decision to endorse Ken Paxton in the Texas Senate race has left many Republicans fuming.Paxton, Texas’s scandal-plagued attorney general, is in a runoff in the state’s Republican primary against incumbent John Cornyn, who has the support of many of his Senate colleagues. Senator Lisa Murkowski of Alaska reportedly told The Hill that she was “supremely disappointed” by Trump’s endorsement, adding, “I don’t understand it.”Murkowski also said that Republicans will likely have a tougher time retaining the seat against Democratic nominee James Talarico, who is polling very well.“Based on the numbers that I’ve seen, yeah,” Murkowski said, regarding the risk that the GOP will lose the Senate. “How does that help strengthen the president’s hand when we lose a state like Texas?”Senator Susan Collins said that she didn’t understand why Trump endorsed Paxton, calling him an “ethically challenged individual” due to his many scandals, which include defrauding investors in a tech startup and an extramarital affair leading to his wife divorcing him on “biblical grounds.”“John Cornyn is an outstanding senator and deserved in my judgment the president’s support. Obviously it’s the president’s call but I’m disappointed that he did it,” Collins told The Hill.Senate Majority Leader John Thune, who for months tried to lobby Trump to support Cornyn, had a serious expression when reporters asked him Tuesday about the president’s endorsement, only saying, “It’s his decision.” Senator Roger Wicker walked into a lunch meeting with his head bowed and ignored reporters’ questions about the endorsement.“I’m speechless,” Senator Rob Johnson told CNN’s Manu Raju when asked about Trump’s choice, taking a long pause before answering, adding that he “really [had] no comment.”Unlike his colleagues, Senator Lindsey Graham was optimistic, telling Raju that “you don’t have to be a rocket scientist to figure out the pathway for Paxton is there, but it’s more uphill, and it will cost more.”In Trump’s own words, “Ken is a true MAGA Warrior who has ALWAYS delivered for Texas, and will continue to do so in the United States Senate.” In contrast, while Trump said Cornyn is a “good man, and I worked well with him,” the incumbent senator “was not supportive of me when times were tough” and “was very late in backing me in what turned out to be a Historic Run for the Republican Nomination, and then, the Presidency, itself.”If Trump’s endorsement propels Paxton to win in next week’s runoff, Democrats may have a better shot at winning the race, as Paxton’s scandals give him a lot in common with the president. But Texas is a strong Republican state that voted for Trump three times, so nothing is certain.