This commentary originally appeared on The Hill.

Please understand this: I've never taken the Never Trump blood oath.

I deeply respect this decision that many other conservatives have made, though. I understand it.

Instead, I've tried to offer thoughtful analysis and considered criticism when necessary.



Since U.S. Sen. Ted Cruz (R-Texas) dropped out after the Indiana primary, I've repeatedly described myself as an undecided voter.



I still am.



But the past three weeks have brought me to my breaking point.



As a Republican operative who has worked in the George W. Bush administration, for two U.S. senators and a governor, and on campaigns in 14 states over 15 years, I want to see Republicans succeed.

I'm just not sure Donald Trump does.



No major party nominee for President has had as disastrous a period of time as Trump has since the conventions began.



Democratic nominee Hillary Clinton's tenuous 3-percentage-point national lead when the conventions began is now a durable 8-point national lead, and growing.

She is fixing her problems: improving her likability, unifying the Democratic Party, baiting her opponent, and reaching out to Republicans and independents. All while running an effective national campaign.



Trump is making his problems worse. He's doing nothing to win the votes of Hispanics, African-Americans, millennials or college-educated women.



He's wasting precious time in states like Colorado, Connecticut and Virginia, which are gone.

He's picking fights with sympathetic Americans (like the Khan family) and making outrageous and false statements (claiming he saw an Iran video that doesn't exist, calling President Obama the "founder" of ISIS, the Islamic State in Iraq and Syria).



He's failing spectacularly at making Clinton play any defense, or even letting any news cycle exist without him dominating it.



Recent negative stories that should dominate the news for days only play for a few hours, as Trump opens his mouth and inserts his foot, almost intentionally.

These recent stories were all subsumed by Trump's latest outburst:



Clinton falsely claiming the FBI director said she told the public the truth about her private server and email practices.

The $400 million cash ransom payment to Iran

The Obama administration's Department of Justice choosing not to open a public corruption investigation into the Clinton Foundation.

Weak economic reports on gross domestic product growth and productivity.

A story detailing a billionaire Clinton Foundation donor who sought a favor from the Hillary Clinton-led State Department.

Indeed, the past two weeks should (and could) have been very bad for Clinton, bringing her back down to Earth after a strong convention.

Republicans have been prepared to accept a Trump loss within an acceptable range of less than 5 points, which would still allow them to hold their crucial House majority and give Senate incumbents a chance to hold their seats.



That type of loss now appears unlikely, as a modern landslide Clinton win looks likely.



Keep this in mind: Barack Obama only beat John McCain by 7 points in 2008, and that was with an incumbent president with approval ratings in the 20s in the midst of a global economic meltdown.



Clinton very well may win this election in an 8-12 point range, which would qualify it as a landslide win in the modern era.



How is the outsider candidate blowing a change election?



If Trump would make himself scarce, by giving more disciplined policy speeches, fewer rallies with shorter speeches, and more quiet time studying policy and preparing for the debates, he would benefit.

Republican voters need to be reminded how much they loathe Clinton, but they can't while Trump dominates the news every single day.



Sadly, there are few reasons for encouragement.



Trump won't change. Won't pivot. Can't be disciplined more than a couple days. Doesn't care about damaging the GOP.

And now, most disconcertingly, he told radio host Hugh Hewitt that he is prepared to lose the election if it happens.



Not even losing will make him see the truth or change direction.



While sunshine pumpers like Sean Hannity, Laura Ingraham and Ann Coulter continue to pretend everything's fine, any honest reading of the data tells us that Trump is headed to certain defeat.



His image is underwater by more than 30 points. I have never seen a candidate in such a position, at any level, win an election.



Your base won't be as enthusiastic, your turnout won't be as high and, most importantly, undecided voters will break sharply against you.



I sympathize with the impossible position in which the Republican National Committee (RNC) finds itself. It's too late to remove him from the ballot. The RNC can't fully embrace him because it will hurt candidates in tough races. But it also can't entirely break from him and lose his support base. It's a no-win situation.

Meanwhile, the RNC needs his celebrity and some of his time to continue raising huge dollars for its joint fundraising account to help the entire GOP ticket.



My fear is that this will get worse before it gets better.



The campaign doesn't exist. They can't control the candidate. The candidate isn't learning or growing. And he thinks he's winning, despite all evidence to the contrary.



I'm at the end of my rope.



I am deeply concerned that Trump's campaign will be an extinction-level event for the GOP, wiping out hard won electoral gains built over a decade.

The potential exists for Trump to do incalculable damage to the party and its future.



We may have miscalculated on one thing about Trump: That he wants to win.



How do you help a candidate that doesn't want to win?