I wonder if it is possible to have a "symbolic effect" on somebody so self-interested as John McCain. If he wants to run again, he will.
Nobody else counts.
I am thinking it might encourage some other ambitious guy to run for the job. Someone like Cruz who has some thing on the ball and who has the time, energy and seed money to go around the state and talk to people. It is true that all politics is local. Can we ignore how Cruz was able to win in Texas, and how Santorum, on a shoe string, was able to win in Iowa ? Of course, Cruz is, as a debater, on the level with Lincoln or Douglas or Clay, but Santorum was just a hack who acquired an insight into the way that ordinary people think.