Yeah, yeah, I know: “They had two Democratic senators when McCain and Flake were there.” Har dee har.

The dirty little secret about Maverick and Flake is that they almost always voted with Trump and McConnell. There was one enormous exception to that rule, when McCain voted no on ObamaCare repeal, but on most legislative matters and judicial confirmations they were on the team.

Kyrsten Sinema and Mark Kelly won’t be. And if you believe this new poll from OH Predictive Insights, those are the two people who’ll be representing Arizona in the Senate in 2021.

Retired astronaut Mark Kelly leads [Sen. Martha] McSally, the retired fighter pilot-turned-politician, by a 46 percent to 41 percent margin, according to the poll conducted by OH Predictive Insights, a Phoenix-based pollster, and released first to The Hill…

McSally has fallen behind, the poll suggests, as President Trump’s standing takes a hit in Arizona. Just 47 percent of likely voters in the state approve of Trump’s job performance, down from 50 percent in May and 54 percent in October. His disapproval rating has risen from 46 percent last October to 52 percent today…

The poll shows a dangerous trend for McSally, who now trails Kelly by 9 percentage points in Maricopa County, home to about 3 in 5 Arizona voters. In the group’s last poll, McSally trailed Kelly in Maricopa by 5 points…

Kelly leads virtually every key demographic group. He runs 5 points ahead of McSally among men, by 6 points among women, by 2 points among white voters and by 18 points among Hispanics.

Maricopa County was the difference in McSally’s race last year against Sinema, handing Sinema an advantage of 61,000 votes in a race she won by 56,000 overall. McSally’s not only losing badly there, she’s falling further behind. Kelly’s beating her in fundraising too, having taken in $8.4 million this year as of July 1 compared to McSally’s take of $5.5 million. I wonder what happens if the next month or two of polling looks just as bad, or worse, for her. Will McConnell panic and try to have McSally replaced as the nominee? Maybe get Trump to appoint her to an ambassadorship or a cabinet vacancy somewhere and try to talk Doug Ducey into the race?

Trump’s doing McSally no favors, as the excerpt notes, but his job approval is still six points higher than her vote share. How come? No, really, I’m asking. Arizona readers, explain to me why McSally chronically has such trouble in a state that’s still kinda sorta red. She’s staring down the barrel at the moment of a dubious distinction, losing Senate races in two consecutive elections in a state that should favor her. I realize she hurt herself on the trail last year when she withheld praise for an ailing John McCain, fearing that it might complicate her effort to hold off a populist insurgency in the primary, but supposedly she’s made peace with the McCains and now enjoys the advantage of incumbency. It’s not like she’s hidden herself away as a member of the Senate either in the short time she’s been there either. She introduced a bill last week in light of the El Paso massacre that would make domestic terrorism a crime, legislation that’s already attracting interest. She’s also stood out on the subject of sexual assault in the military, revealing that she was assaulted herself while also going to bat for Trump’s nominee for Joint Chiefs vice chairman by questioning the assault allegations against him.

Plus, she’s a distinguished Air Force veteran. So what’s the problem? Why is all of that not good enough for a state capable of electing McCain and Flake?

For all the hype about her supposedly being a bad candidate, I wonder if it’s simply her misfortune to have run into two very good candidates at a moment when her state is trending towards the center. Sinema is likable and positioned herself cannily as a centrist last year, a reputation she’s continued to cultivate in the Senate on matters like immigration. Kelly is famous twice over, once as an astronaut and the other as Gabby Giffords’s husband, and has spent the better part of 10 years leading gun-control initiatives that have endeared him to Democratic voters. He has connections in the party and the sympathy of Arizona voters, and he’s running in the midst of demographic change in his home state that’s steering it towards becoming a toss-up a la Colorado rather than a red stronghold like the deep south. On top of all that, McSally’s saddled with a relatively unpopular president from her own party who’s distinguished himself by engaging in an ongoing feud with the most famous politician to come out of Arizona since Barry Goldwater, even though that politician has been dead for a year now. Are we sure McSally’s a bad candidate rather than a victim of unusually bad circumstances?