It was the same in 2020 with people flocking from Buttegieg, to Klobuchar, to Mark Kelly, to Kamala, to Biden, and so on. They are glomping onto anything.
Mark Kelly is a contender in many respects: he's a former astronaut, he has connections to the Chocolate Messiah, and his wife is Gabby Giffords. He's been floating presidential runs for at least 10 years now and has some name recognition. However, he has 3 problems: he's a white male, he is against semi-auto rifles (which is no longer a winning issue after proglibs armed themselves post-2016 and got redpilled about guns), and he has a temper. Kelly is easily put on tilt and does a lot of theater kid performative shit. I don't think he'd perform well in a debate with someone like JD Vance, who stays calm under pressure and doesn't back down. Kelly has basically been insulated in Arizona and I don't think he has any idea how Republicans actually think since his ideas of Republicans are stuck in the John McCain-Obama era.