2016 Senate: Republicans maintain it?

[Vosem]

The idea that 2016 is as bad for Republicans as 2014 is for Democrats is an exaggeration, but that doesn't mean that it won't mostly be Democrats on offensive in 2016. Republicans hold relatively few seats in actual left-wing states (the only one, actually, is Kirk in Illinois, who is pretty personally popular, though that probably won't save him) but there's lots of seats in swing states (Johnson/Portman/Toomey/Ayotte/Rubio/Burr/Grassley/McCain/Paul) which Republicans are all basically favored to maintain, but which could fall if the incumbent retires or the Democratic candidate runs a good campaign, and will begin falling like dominoes in a Democratic landslide year. The question for 2016 is the environment -- a neutral one means the Senate staying about the same, or maybe very small Democratic gains, but a Democratic environment could mean massive gains for the Democrats. (Unlike 2014, where even in a neutral environment this November Republicans might still gain the Senate because of how skewed the map is). Republicans do have two options, more or less, for gains (Nevada and Colorado, probably in that order), but it'll take either Sandoval running in NV or a very good Republican environment to pick either of those up, and in the latter case Democrats retaking the Senate probably won't be a real concern.