The main issue with these forecasts is that most of the time they seem too biased toward incumbents. I highly doubt Evers has a 60% chance of winning, he could very well win but he's probably a slight underdog right now. Same with Kelly, I don't think she has a 40% chance of winning, maybe like 20% or something. It works the other way around too. I think Kemp is the favorite but I wouldn't quite put it at 85% chance.
The problem is 538 made this mistake before. In 2018, their Senate forecast was skewed towards incumbent Democrats, partly because their fundamentals calculation was more favourable to them than the polls because it assumed incumbency would beat partisanship more than it did. That was an understandable mistake then because those incumbents won in a worse environment in 2012, but it could have been learned from. The fundamentals forecast now should then be highly weighting partisanship and not showing much of an incumbency boost or split-ticket voting.
