There is emerging understanding that - even with the gerrymandering - the Democrats seem in great shape to take the House and maybe the Senate. Morris looks at how the big prognosticators tend to skew against the "out party" in the midterms. Basically, if you're the party out of power, the big raters like Cook and Sabato tend to underestimate the gains that you're going to make. In his analysis, "Toss Ups" aren't really toss ups at all, but lean to the out party by a lot. This could be important - if it holds - if these raters move more races into the toss-up category.
The other thing that seems to be happening is that Democrats tend to better when their actual candidates are polled as opposed to the generic ballot. Some of this is enthusiasm, but I think it also represents the fact that "Democrats" are an unpopular party, whose unpopularity is only exceeded (by a lot) by the Republicans. So, you have a lot of people saying that they don't necessarily support Democrats, that doesn't mean that they won't vote for Talarico. Democrats in red states are not a strong "brand" but individual candidates like Mary Peltola matter.
I don't want to suck on the hopium pipe like I did two years ago. Still, you have a rising confluence of events and a president who is weaker than he seems and historically unpopular.