[Go Gordon]

Prediction: The incredibly piss-poor candidate McSally loses to Gallego in 2020 and Governor Ducey runs against Gallego in 2022 (and beats him) when his new term as Governor ends.

If Gallego wins in 2020, then Ducy would have to wait until 2026 to run against him, not 2022.

[House Atreides]

Prediction: The incredibly piss-poor candidate McSally loses to Gallego in 2020 and Governor Ducey runs against Gallego in 2022 (and beats him) when his new term as Governor ends.
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If Gallego wins in 2020, then Ducy would have to wait until 2026 to run against him, not 2022.
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Nope. McCain last ran for Senate in 2016; a race which he, of course, won. That Senate seat is scheduled to be contested (in a regular/non-special election) again in 2022, six years after the 2016 regular election.