Evan McMullin announces his presidential campaign last month in Salt Lake City. (George Frey/Getty Images)

Conservative independent candidate Evan McMullin got an eye-catching endorsement from #NeverTrump conservative activist Erick Erickson. Erickson acknowledges McMullin is extremely unlikely to win but argues nevertheless:

Evan McMullin may actually serve a more important role in 2016. Though he may not win, he might at least provide disaffected conservatives an excuse to show up and vote down ballot. Saving the Senate and House of Representatives from the Democrats has to be a priority for conservatives, but many are so disgusted by 2016 that they will not even show up in November.

McMullin gives people a reason to show up. He gives conservatives someone they can vote for without holding their nose. He gives people someone to vote for instead of reconciling themselves to voting against someone. McMullin’s candidacy is not the lesser of an evil, but an alternative against evil. For many, that will be enough.

The turnout argument is a compelling one, although many GOP Senate incumbents are doing well, running far ahead of the top of the ticket thanks to ticket-splitters. Sen. Rob Portman (R-Ohio), for one, is ahead by double-digits in most polls, while the presidential race in Ohio is still within the margin of error. However, the chance to vote for McMullin may help some Republicans in competitive House seats in states with no Senate or gubernatorial race. There, the problem of GOP turnout could be addressed, in part, by persuading Republicans disgusted with the Trump-or-Clinton choice to show up.

Erickson’s second reason — the chance to cast a positive vote — may be more compelling. If a Republican voter in one of the 40-plus states that are not competitive at the presidential level cannot abide the Trump-or-Clinton choice, he or she can be happy to vote for a mainstream Republican who is ethically sound. Even in competitive states, a Republican McMullin voter could choose this as a way of rejecting Trump without helping Hillary Clinton. (These voters reject the “binary choice” argument.)

In essence, Republicans in competitive seats scared out of their wits at the prospect of a Trump president (the stop-Trump-at-all-costs voter) may feel compelled to vote for Clinton. Others, whether in “safe” states or unmoved by the possibility that Trump might actually win, may be grateful for the opportunity to cast a vote for McMullin.

There is a third, related argument for McMullin: It’s a shot at the Republican Party that expected every Republican to get in line, a party that decided winning was better than any issue and more important than the welfare of the country. It is a way of saying center-right politics can continue, if need be, without the Republican National Committee, Reince Priebus and the slew of spineless elected officials who are supporting someone they know to be unfit. (Unbelievably, rumors are now circulating that Sen. Ted Cruz is getting ready to endorse Trump — a final flip-flop that would be certain to cement his reputation as a craven opportunist.) It is the starting gun, if you will, in the post-Trump battle that will break out as soon as the winner is declared on Nov. 8.

If Trump loses, no one can be certain whether the GOP will fracture or whether there will be a fight for the corpse of a once great party. Both McMullin supporters and pro-Clinton Republican groups such as R4C16.org will make the case that the future of the right cannot be left to those who sacrificed all principles for partisan loyalty and who allowed conservatism to be tainted by Trump’s racism and misogyny. McMullin, by offering himself as a safe harbor for despondent conservatives and presenting a sane center-right agenda, has earned a leadership role in that struggle.