I follow this election reform stuff very closely.
Alaska and Maine have both adopted a form of ranked choice voting called instant runoff. There are other forms. Each has different effects on candidate strategy. Alaska has a primary stage where each voter just picks one candidate, and then in the general stage the voters can rank the top four candidates. Both stages are non partisan, so the top four will usually be two democrats and two Republicans. In a regular election, you just have to be the first choice of many people. But in instant runoff, you need that, plus you have to be the second choice of a very particular set of people. It is very important to limit the field before allowing ranking this way, because candidates need to know which other candidate they need to target for those second choice votes. They have to play nice with that candidate while going hard on the other candidate.

Said another way, Peltola didn't win with second choice votes. In all likelihood, Begich had more second choice votes than Peltola. Begich was probably the second choice of Palin voters and Peltola voters. But Begich was eliminated, and the only second choice votes that counted were the ones from people who voted for him. Peltola knew this was likely to happen, which is why she played nice with Begich for most of the campaign.

It's obvious that Peltola beats Palin in a one on one contest, assuming those Begich voters show up, but the Alaska authorities won't give us enough info to know if Begich might have beaten both Palin and Peltola in one on one contests. He probably would have.

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