He’s 85. And even if he were half as old as that, this would still be bananas.

“I’m sure getting a lot of people around the state asking me” to challenge Flake, said Arpaio, who served 24 years as sheriff before losing reelection in 2016. “All I’m saying is the door is open and we’ll see what happens. I’ve got support. I know what support I have.”…

“Why do you say ‘wow’?” he admonished, adding: “They just say Sheriff Joe Arpaio comma 85 years old. Why do they always say that?”

Arpaio said he believes “there is discrimination against senior citizens, bigtime” and that “I’m proud to be my age. I work 14 hours a day. If anyone thinks my age is going to hold me back, I’ve got news for them.”

Could Arpaio beat Flake in a primary? Maybe. Nationally, Trump voters view him favorably by a margin of 72/6. But Arizona Republicans aren’t as keen on him as Republicans elsewhere are, having watched how he operates up close for years. Jon Gabriel, a conservative and a resident of Maricopa County, loathes him:

During one three-year period, his Maricopa County Sheriff’s Office didn’t properly investigate more than 400 alleged sex crimes, many of them involving child molestation…

When local journalists delved into Arpaio’s dealings, he had them arrested, a move that ultimately cost taxpayers $3.75 million. We paid $3.5 million more after the sheriff wrongfully arrested a county supervisor who had been critical of him…

Arpaio’s staff concocted an imaginary assassination attempt on the sheriff, presumably for news coverage. Taxpayers had to pay the framed defendant $1.1 million after he was found not guilty.

The sheriff’s department misspent $100 million on the sheriff’s pet projects, and wasted up to $200 million in taxpayer money on lawsuits. Yet he still found money to send a deputy to Hawaii to look for President Obama’s birth certificate.

Arpaio lost a sheriff’s race in Maricopa County last year to a Democrat by nearly 11 points. Trump won Maricopa by nearly three points. Many a Trump supporter in that county agreed with Gabriel sufficiently to have split their ballots rather than send Sheriff Joe back for another term. Flake is deeply unpopular statewide and has made an enemy of Trump, so anyone — including Arpaio — would stand a chance against him in a primary, but it’s not the lay-up that populists might believe. Especially if Arpaio is one of only several primary challengers, dividing the anti-Flake vote among them.

And if Arpaio did defeat Flake, it might mean a Democratic walkover in the general election. A poll taken of Arizona last week found just 21 percent supported pardoning Arpaio on the criminal contempt charge he was convicted of. Fifty percent opposed it. There may be no Republican across the state whom Democrats despise more viscerally than Arpaio, and almost certainly no Republican whom Latinos would mobilize more eagerly to defeat. In that sense he’d be the perfect Trump-picked primary challenger, an authoritarian populist who’d either damage his Republican opponent in a losing effort or who’d beat Flake only to lose handily to a Democrat himself.

Oh, and he’s 85. It’d be the most GOP thing ever to nominate a guy to be a first-term senator who’s deeply unpopular, a Birther, was facing jail time until he was pardoned, and would be in his 90s before his term is complete, just because he’s a populist who’s ruthless with inmates in his custody. So, sure, let’s do it.