Stacy Abrams did something extraordinary. She got a record number of early voters out and new voters registered. The strategy almost paid off for her, too, and I suspect the only reason it didn’t result in a win is that she suppressed her own vote with all the talk and news stories of “voter suppression” actually had the opposite of the intended effect and convinced black voters to stay home out of a fear of hopelessness.
In Texas, we saw Ted Cruz struggle a lot more than he should have. Democrats showed up in force in Texas, and that bodes ill. Republicans eeked out a win in Florida, but it could have gone the other way. You had a Democratic victory in Doug Jones (Alabama) and John Bel Edwards (Louisiana) based largely on flawed candidates (Roy Moore and David Vitter, respectively) and Republicans simply did not turn out for them.
If Texas, Florida, and Georgia run candidates who were more appealing to the center, those races could have flipped easily.