Six years and several political lifetimes ago, Democrats across the country were under the spell of Betomania. A young congressman from El Paso, Beto O’Rourke, had seized the attention of young people, donors, and glossy magazine editors with his vigorous, gonzo challenge to Texas Sen. Ted Cruz, a prized archvillain to liberals (and plenty of D.C. Republicans). O’Rourke smashed fundraising records and made such a star turn that, even after losing the race to a widely disliked senator, he was