The latest from Charlie Cook:
The Cook Political Report’s current outlook is for a Republican net gain of at least 40 seats. A turnover of 39 seats would tip majority status into Republican hands. At this point, only 209 House seats are Solid, Likely or Lean Democratic, while 181 seats are Solid, Likely or Lean Republican, and 45 seats are in the Toss Up column.
More here.