A popular, well-known candidate could co-opt a minor party and inherit its ballot access. But with money and expertise, starting a new party isn’t out of reach: The financier Peter Ackerman and the political reformer Kahlil Byrd led a 2012 effort, Americans Elect, that got on the ballot in a majority of states (staged as an effort to build a national primary, Americans Elect didn’t nominate a candidate).

Given that two-thirds of Americans don’t believe President Trump to be trustworthy, almost anyone could be a candidate for a serious third-party run if he started early enough to gain full ballot access. Ask your neighbor whether the idea of a Joe Biden-Ben Sasse independent ticket is appealing — with Mr. Biden pledging to serve only four years (to address concerns about his age). Jeff Flake or Bob Corker could be a contender.

Another possibility: a business executive with a record of sound leadership, moral authority and a quick wit: the financier David Rubenstein, Ginni Rometty of IBM or Jamie Dimon of JPMorgan Chase, perhaps? How about a centrist Republican governor like Larry Hogan of Maryland, John Kasich of Ohio or Charlie Baker of Massachusetts? And then, of course, there’s Oprah.