This is what I think will happen; worst case scenario for the Dems could see the loss (compared to my map) of CT, PA, NH, MO, OH, IL, CO and maybe an upset or two, which would still leave the GOP 2-3 short of a majority (since a 50-50 tie would still favor the Dems).
With the map I made the Dems would have 62 or 63 seats (I can't call Ohio either way right now) which would leave Mary Landrieu or Tom Carper as the 60th most liberal vote (according to Voteview's rankings of the 110th Senate)...sounds good to me.