I'd say about 35%.
CO/AL swap unless something unexpected happens, which keeps us at the 53/47 baseline.
Aside from CO, AZ is the lowest hanging fruit. Flips depending on the outcome of the presidential race in the state, but Kelly is strong enough and McSally weak enough that I think PresiDem could lose marginally with this seat still flipping. 52 - 48
NC falls next. PresiDem would probably need to be winning by a solid but not spectacular margin. 51 - 48
Then, with a PresiDem victory, they need one of GA/ME. TX may well end up being competitive but if it falls then GA probably does as well. IA could become competitive if it's a wave but probably not and MT depends on Bullock.
So one of GA or ME has to be cracked to get the majority. Even if they don't land Abrams, the Dems have a decent bench in GA, and Perdue is not the strongest incumbent. However, the demographics might not be right yet and the turnout differentials have to be pretty heavily in the Dems favour for them to stand a chance. In ME, they have to get a strong candidate (Golden would be the best option) and get to work on Collins' image now. But, as we all know, the Democrats aren't exactly stellar at this whole politics business and will probably let her glide through because of 'moderatism' or some guff like that.
Overall, it's not impossible by any stretch of the imagination, but it'll take some work.
NC votes generally six points to the right of the rest of the country so a 51/48 D wins wouldn’t be enough to flip NC
