As polls show Republican presidential candidate Jeb Bush slipping, and though his donors may be worried, he’s certainly not, at least visibly. Speaking to ABC News today, Bush offered an anecdote about a previous GOP candidate whose chances seemed slim. “This time, eight years ago, John McCain was traveling through the Atlanta airport. I saw him and he had no aide, no person, [he was] by himself because his campaign was supposed to be ended," Bush said of the Arizona senator. “He won the Republican primary that year. This is how the process works; you have to go earn it.”...