Mike Murphy has never been shy when it comes to Donald Trump. A longtime Republican political consultant, Murphy led Jeb Bush's Right To Rise super PAC in the 2016 primary season and, in that role, did everything he could to slow the real estate mogul. It didn't work. But Murphy, who has spent decades working to elect and reelect dozens of senators and governors, believes that Trump's number is just about up -- and that his reckoning will begin in earnest in Tuesday's Wisconsin primary. My conversation with Murphy -- conducted via email and edited only for grammar -- is below.

FIX: You tweeted recently that Wisconsin "is going to be Trump's Stalingrad.” Explain why you think what happens Tuesday in Wisconsin will matter so much — and so much more than all the votes that have come before it?

Murphy: Wisconsin is a big primary, not a caucus, and a good measure of what Republicans are thinking right now. If Trump has jumped the shark like I think he has, a big loss in Wisconsin will prove the point and change the media narrative. The media will go from treating Trump like an amazing Dancing Mule Act — “Wow, I’ve never seen a mule dance the Jitterbug like that! Amazing! Get him a TV show! Call the neighbors!” — to asking, “Why is that mule crapping on the carpet? Who brought that stinky creature in here?!” Being a big loser is Kryptonite to Trump’s overall con, and now, as the new Bobby Riggs uniting America’s women in their hatred of him, Trump has stink all over him. So the media narrative will change from unstoppable rise to brutal fall, and Trump will not handle that well. His numbers will drop, and the remaining primaries will be like quicksand for him. He’ll thrash and howl and make things worse. I thought this race would reflect the GOP's epic struggle between the mathematicians and the priests. Instead, this year has come down to a battle between a priest and a charlatan, and once found out, charlatans find themselves in big trouble very quickly. It usually ends in a funeral pyre surrounded by cheering priests.

I’ve been dubious that Trump would get to 1,237 anyway — since it requires his vote share in April to increase, and I think it will decrease now — but if he takes a big hit in Wisconsin and he starts to decline, he won’t be able to put a first-ballot win together and after that, he will be toast. I’d love to be a fly in the room in June when one of his yes men explains to Trump that a large number of his pledged first-ballot delegates are actually Ted Cruz people … it’ll be like a Downfall remix.

FIX: Let’s assume Trump doesn’t get to 1,237 delegates before the convention. What’s the best-case scenario for the broader Republican Party coming out of Cleveland?

Murphy: Somebody other than Trump, Cruz or Mark Levin as nominee, but I don’t see a path. I think it’ll be Cruz. He’ll be second in delegates, and he is organically what the biggest hunk of the convention floor will want. An open convention will have the dynamics of a caucus. Only way that changes is if either Trump or the GOP regulars somehow overwhelm the delegate selection process, which I think is highly unlikely. It is true that Kasich is the one guy still running who could win a general election against Hillary Clinton, but it’s academic since he won’t have the delegates going in, and I doubt he’ll have much appeal to the conservative activists who make up the majority of the delegates on the floor. So I think this year is about trying to hold the Senate. Then we have to rebuild the party for 2018. If I were Reince [Priebus] I’d be tempted to ban all TV coverage of this convention and deny it exists.

FIX: Can Ted Cruz beat Hillary Clinton in November? If so, how exactly?

Murphy: It would require a mighty assist from the Justice Department. I don’t think Cruz is a strong general-election candidate at all. But anything is better than Donald Trump. I’m glum about it, but Cruz reflects the priests' standard assertion that the general election is just a larger version of a Republican primary. At least a Cruz nomination will give us a way to test that theory and hopefully learn from the result.

Donald Trump says he can't wait to take on Hillary Clinton in the fall, but here are three reasons why he could lose a general election. (Sarah Parnass/The Washington Post)

FIX: In the 2012 RNC autopsy report, there were clear recommendations to tone down the rhetoric on immigration and find a way to be for a comprehensive immigration reform plan. Four years later, Trump has taken his hard-line stance on immigration and wall-building and put it at the center of his front-running campaign. What does that tell you about (a) the state of your party and (b) the disconnect between party leaders and the base?

Murphy: There is a big disconnect. The mathematicians have the facts, but not the primary votes. The incentives to win the GOP nomination today are totally misaligned with what is needed to win a general election. We must either develop a positive, reform conservatism with real appeal to the general-election electorate or accept the dire reality that we are not going to soon see the inside of the White House. This year we are testing exactly what not to do. Shame on us.

FIX: Finish this sentence: Nominating Donald Trump in 2016 would mean ________. Now, explain.

Murphy: ... a lost decade for American Conservatism. Trump would be an absolute train wreck. We’d lose the presidency in a landslide as well as lose vital Senate and House seats. Our Republican brand would become even more toxic to general-election voters. Our conservative cause would take years to recover, and a Clinton presidency would be an American version of the U.K. in the 70’s under Labour governments: a grim cocktail of stagnation, decline, misery and pain.

What Donald Trump is doing on the campaign trail

U.S. Republican presidential nominee Donald Trump speaks at a campaign event at Trump Doral golf course in Miami, Florida, U.S. July 27, 2016. REUTERS/Carlo Allegri (Carlo Allegri/Reuters)