In one of his first rallies since winning President Donald Trump’s endorsement in his Senate race, Ken Paxton told the crowd he wanted to try something new. The Democratic nominee, James Talarico, Paxton said, would be the “most radical US senator from Texas, maybe in the whole country, ever, so I wanted to test a few nicknames tonight and see if you can help me.” The suggestions from the audience started flowing as Paxton passed the mic around. “Low-T Talarico.” “Tofu Talarico.” “Tala-freak-o.” “Soy boy!” a man yelled out unprompted. The food references came from an already burgeoning Republican talking...