Here's a comparison, with the same Class 1, no less: in 1982, the GOP had come off of a landslide victory in 1980 (that Trump didn't have) with a charismatic president who was popular for most of his tenure and was a good communicator. (none of which applies to Trump) They only had to defend 11 seats, and the Dems had to defend 22. 22 Senate seats from mostly Reagan states, like Montana, Wisconsin, Ohio, Tennessee, and Florida. In that midterm election, Democrats walked away with a net gain of one seat while the GOP broke even. I don't expect 2018 to be any harsher on the Democrats
Not to mention that in 1982, of all the Republicans who won reelection or picked up a seat, 7 races were pretty close, some very much so:
Missouri
(John Danforth) 50.8% - 49.1%Minnesota
(David Durenberger) 52.6% - 46.6%Nevada
(Chic Hecht - Rep pickup) 50.1% - 47.7%Rhode Island
(John Chafee) 51.2% - 48.8%Vermont
(Robert Stafford) 50.3% - 47.2%Virginia
(Paul S. Trible Jr. - Rep pickup) 51.2% - 48.2%Connecticut
(Lowell Weicker Jr) 50.4% - 46.1%-
@Eharding - if you think it's impossible for Republicans to come up short in 2018 with that map, consider that Democrats won those races once before in the first place, and that a map that was supposed to be gold for Democrats last year didn't work out as well as it looked on paper. Sure, some Democrats in 2012 got real lucky, but now they have some more luck of their own by running as incumbents in a midterm of who will probably be an unpopular incumbent president. A large net gain is likely not in the cards for Republicans if what we've seen so far continues into the future.
For as bullish as people accuse us Democrats of being now, you guys sure have some hyper-optismistic views on your side, despite history showing time and again the pains an unpopular president inflicts on their party. They aren't running against an equally unpopular Clinton next time. There won't be a single target for deflection anymore.