It wasn’t supposed to go like this. When Jeb Bush announced a exploratory committee for the 2016 Republican primary exactly one year ago Wednesday, the plan was simple: Keep Mitt Romney out of the race, lock up the establishment money early and ride Bush’s experience as Florida governor and a big war chest to victory. And for a little while, the plan almost worked. Bush became the front-runner, and though his lead wasn’t as strong as his campaign might have liked, he seemed to have locked up the big donors and maintained a steady share in the polls. Then Donald Trump showed up, and the campaign quickly got away from Bush. In debate after debate and on the campaign trail, Bush stumbled and fumbled away his support. He came off worse in clashes with Trump and with Sen. Marco Rubio (Fla.). He now sits fifth in Iowa, sixth in New Hampshire and at 4 percent nationally.