That’s the conventional wisdom. “She always seems to be able to draw aces,” former Sen. John Danforth told The New York Times.

“She’s a lucky duck,” former Missouri GOP chairman John Hancock told Politico.

Both men were referring to the impact of the Eric Greitens scandal on this year’s Missouri Senate race. State Attorney General Josh Hawley, McCaskill’s likely Senate opponent, is mired in a bitter dispute with the governor, splitting the party in two.

McCaskill also walked the sunny side of the street in 2006, when she beat Sen. Jim Talent in an anti-George W. Bush wave, and in 2012, when her opponent, Rep. Todd Akin, repeatedly stuck his foot in his mouth.

Sure, there’s some luck in that record. But Republicans really miss the point — and risk a third straight defeat — if they believe McCaskill’s victories are simply the result of her good fortune and not their own grievous electoral mistakes.

Akin’s candidacy in 2012 is a good place to start. Virtually every Republican in Missouri knew Akin would be a rhetorical time bomb that fall — he once said he pined for a “ladylike” McCaskill in a debate. Later, he compared her with a dog.

And of course, Akin’s reference to “legitimate rape” provoked a national firestorm and calls for him to leave the race.

Those statements, and others, weren’t accidents. McCaskill wasn’t lucky when Akin made them. They were a clear reflection of what Missouri Republicans wanted during that tea party year.

The state’s GOP leadership knew it. Yet those Republicans did nothing to stop Akin until after the primary, when it was far too late.

Missouri isn’t the only place where this happens. Was Democrat Doug Jones lucky in Alabama when Republicans nominated Roy Moore for a Senate special election in 2017? Of course not. Moore was a disaster.

In 2012, Indiana’s GOP voters picked tea party favorite Richard Mourdock instead of incumbent Sen. Richard Lugar. Predictably, Mourdock stumbled over a rape question — and lost to a Democrat. In Indiana.

That brings us to Greitens, Hawley and McCaskill in this election cycle.

Greitens’ political approach — self-centered, arrogant, entitled — isn’t a bug in the governor’s makeup; it’s a feature. Republicans clearly knew that about the candidate in 2016, and they embraced him.

It isn’t an accident or bad luck that Greitens is a political disaster now. The governor didn’t slip on the stairs and wind up in the basement with a mistress. He didn’t accidentally find a donor list behind the couch. He didn’t stumble upon thousands of dollars in secret donations or mistakenly attack members of his own party.

It isn’t McCaskill’s good luck that such a person leads the Missouri GOP. It’s the result of the party’s poor judgment in picking Greitens in the first place.

That puts Hawley in a tough spot. He wants to appeal to suburban moderates appalled by Greitens’ behavior, while not alienating the governor’s supporters in rural areas.

Increasingly, Hawley seems to understand he must pick a side. And he isn’t picking Greitens’.

McCaskill would probably agree that luck has had little to do with her career. She’d claim skill: She says she helped Akin win the GOP nomination in 2012, a claim so McCaskill-like that the trophy should be retired.

But it isn’t McCaskill’s intelligence or luck that explains her political career. It’s Republicans’ insistence on nominating deeply flawed candidates to lead their party. They will have no one to blame but themselves if she wins again in 2018.

By Dave Helling, Kansas City Star