Despite Vice President John Nance Garner's notorious description that the vice-presidency as not worth a pitcher of warm spit," the fact is that the office, and who holds it, matter enormously.
That was true in Garner's time and even more so today. Nine vice-presidents before him had advanced to the presidency, six by succeeding a deceased president.
Five more men have been added to that list since Garner's day, three because of the death or resignation of the elected president.