ZW: These days a major-party presidential candidate picks his or her running mate. This significantly weakened the position, making the vice president a stand-in and not the second-most-qualified politician for the presidency. That is the single most important role of any vice president, the ability to step into the president's shoes. The vice president used to be a punchline, and you can watch an entire HBO series based on that premise! Thomas R. Marshall, vice president under President Woodrow Wilson, said, "Once there were two brothers: One ran away to sea, the other was elected vice president.

Source: CNN June 27, 2020 11:26 UTC