Sure, Dems could lose the Senate. I could easily see six seats falling. However, Democrats could really only fall another ten seats in the House. You gotta remember that when Republicans Gerrymandered in 2012, they had to make the remaining Dem seats safer in order to protect their 2010 gains. That is what insulates Democrats from a further major falloff there.
All correct, except that I would move the stop loss number for the Dems in the House up to a score myself. One problem is that many of the losers from Obamacare tend to be swing voters.
I could see maybe 15 if things got horrendous. Even then, Republicans would have to go a bit beyond swing voters and get some Dem base crossover support.
There are 15 D-held seats in R+ CPVI seats (and 6 in EVEN seats). Sure, quite a few would survive even a wave, but the point is that there's still a fair amount of fertile ground. Or put another way, Republicans would net 10 seats if all they did was tie the popular vote and have a high correlation between Presidential and Congressional votes.
But I agree in the sense that getting beyond 15 would start to get tricky, because there aren't very many swingy D+ seats (only 13 from D+1 to D+3, which by comparison is less than the number of R+6 seats or D+8 seats alone). Still, you don't have to make deep inroads among Dem base voters to win those sorts of seats. Low Democratic turnout and/or winning swing voters by a large margin would do it. Republicans won quite a lot of seats with those numbers in 2010 that way.
