Arizona Republican Rep. Martha McSally, curled up on the couch with her dog, announcing via a video on Twitter that she had conceded the state's Senate race to fellow Rep. Kyrsten Sinema, a Democrat.

"I wish her all success as she represents Arizona in the Senate," said McSally of Sinema. "I am convinced Arizona is the best state in the country and our best days are still yet to come."

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It was a strikingly different tone than President Donald Trump took toward the race in a tweet over the weekend.

"Just out — in Arizona, SIGNATURES DON'T MATCH. Electoral corruption - Call for a new Election? We must protect our Democracy!," Trump tweeted , despite zero actual evidence of election fraud or even the allegation of the fraud. And a very different approach than that of the Senate Republican campaign arm, which emailed reporters after the election suggesting that election officials in Maricopa County (Phoenix) were trying to "cook the books" for Sinema.

And the McSally concession came before all the votes were counted. According to CNN figures , Sinema held a 38,000-vote lead (out of more than 2 million cast).

So why did she do it -- particularly given that the President of the United States seemed convinced that she should have kept fighting?

The answer is that McSally is playing the long game. Or given the timing, the medium-ish game.

Remember that Arizona Sen. Jon Kyl, when accepting Gov. Doug Ducey's appointment to fill the seat of John McCain following the late senator's passing, made very clear that he wasn't planning to stick around the Senate all that long. "I have committed to serving at least through the second session of the 115th Congress," Kyl said

"I do know I will not seek this seat in 2020, nor any other office in the future." Kyl told the Arizona Republic earlier this month that he planned to talk to Ducey about his future plan soon. "I have family needs, as well, and so, we'll decide what to do at that point," said Kyl. "I'll talk to the governor."

At a minimum then, we know that there will be another open-seat special election in Arizona in 2020. (That race will be for the remaining two years left on McCain's term; he was re-elected in 2016 and the race for the next full 6-year term will be in 2022.) And McSally, with an eye on that race, likely wants to not look like a sore loser or to keep up a nasty fight in a race she is very unlikely to win. Most voters like their election to end somewhere close to the actual vote and with a clean result -- either way. Continuing to charge at the electoral windmill rarely behooves a candidate's long-term political prospects.

But the truth of the matter is that McSally may not even have to wait that long. Kyl's quotes about his future plans make clear that he was only wiling to pledge to serve until the end of the 115th Congress, which will come to an end shortly. If Kyl resigns his seat in early 2019, it would, again, be up to Ducey, who just got reelected, to appoint a successor to serve until the 2020 special election. McSally is far and away the likeliest pick for Ducey.

And it's not hard to imagine that Kyl wanted to wait and see what happened in the 2018 election before making a decision on when he will walk away from the Senate. With McSally losing, Kyl now likely is further incentivized to leave before 2020 so as to give a Republican the best chance to hold the seat.

"Republican Martha McSally soon could be called Sen. McSally. More than one million Arizona voters wanted to see the former fighter-pilot-turned-southern-Arizona congresswoman in the Senate. Gov. Doug Ducey could grant them their wish. ... Ducey, with one stroke of a pen, could apply some desperately needed salve to the open, gaping wound that is post-election Arizona."

Seen through the lens of her future political prospects, McSally's decision not to fight until the last vote makes a whole lot more sense. She's got an even-money (and maybe better) chance at making it to the Senate sometime in 2019. Why even risk jeopardizing that by fighting out a race that she almost certainly can't win?