Assuming that Sinema does not seek the Democrats’ nomination for the Senate, they will have to decide whether to support her anyway (as they do with, say, Angus King in Maine) or whether to run their own candidate. If they do, that could split the Democratic vote, and help Republicans. But further complications ensue: If a Democrat runs too far left and the Republicans nominate one of the Arizona GOP’s deep bench of nut cases, will there still be a path for Sinema to run down the middle and win?

Ruben Gallego, a progressive congressman who has been laying the groundwork to primary Sinema, possibly with the support of the Biden White House, is now in a delicate position: His party is convinced that he’d be an upgrade on Sinema in the Senate, but so long as she won’t go away and can’t be primaried, he needs to convince them that he won’t be throwing the seat away by running — yet, he also needs to convince Sinema’s donors and potential voters that she is the one helping Republicans. Enter Public Policy Polling. PPP, a progressive outfit known for polls that shape narratives about campaigns — sometimes in disastrously misleading ways — has a new poll out, which appears as if it was commissioned by Gallego or by someone sympathetic to him. …

Of course, listing Lake as the only potential opponent, in the midst of her post-defeat tantrum, is a thumb on the scales. It would be very interesting to test this race with Doug Ducey as the Republican candidate, given that Ducey probably appeals to a decisive segment of the people who would vote for Sinema if the other options are Lake and Gallego.

[Ducey could have run for the Senate this year, though, and against a weaker opponent. He would have clobbered Blake Masters in the primary and likely would have done the same to Mark Kelly. The Senate didn’t appeal to Ducey, however, and it’s far from clear that it will appeal any more in 2024. He might be mulling a presidential run instead.

UPDATE: I originally and erroneously wrote Lake rather than Blake Masters. — Ed]