In general, though, these shifts do not dramatically change this election cycle’s overall landscape, which tilts against the Democrats. The Democrats still have more chambers at risk this cycle -- and limited options for flipping chambers held by the GOP.

All told, the GOP is poised to pick up two or three chambers this fall, though outcomes could range from a Democratic gain of two to a Republican gain of seven or eight.

The current partisan breakdown in state legislatures is 58 Republican-held chambers and 40 Democratic-held chambers. That's a slightly smaller margin than the 61 chambers the GOP controlled in 2012. Historically, though, it's a high GOP total. As recently as the run-up to the 2010 election, the Democrats held a 62 to 36 advantage in chambers.

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That said, the relatively small number of vulnerable chambers limits the Democrats’ downside risk this year. And the modest number of adjustments made in this update contrast with the 2006 and 2010 cycles, when national partisan waves developed. Those years, Governing was shifting large numbers of chambers right up through Election Day. The Democrats’ challenge stems less from a Republican headwind and more from the map they have faced since the beginning of this cycle.

http://www.governing.com/topics/elections/gov-legislative-handicapping-update-late-october.html