The Pew Charitable Trusts

More state legislative chambers will be up for grabs in November than in any electoral cycle since 2002, according to a state-by-state electoral forecast published this week on the website of Governing magazine. That's bad news for Democrats, who have more to lose than Republicans, the analysis finds.

The forecast — done by state elections analyst and occasional Stateline contributor Louis Jacobson — finds that 18 states have at least one legislative chamber that could change hands politically in the fall. (Click here for a closer look at these 18 states.)

Meanwhile, at least three states — Alabama, New Hampshire and Wisconsin — could see both houses of their legislature change hands, Jacobson predicts, rating both chambers in each state as "tossups" heading into November. If chambers that "lean Democratic" or "lean Republican" are included, six more states — Colorado, Iowa, North Carolina, Alaska, Montana, and Tennessee — could see a wholesale turnover.

For Democrats at the state level, that spells a potential disaster, according to Jacobson.

"Currently, the Democrats have 21 chambers in play, compared to just four for the Republicans — a burden five times as heavy for the Democrats," he says. "None of the previous five cycles - which included two national wave elections (2006 and 2008) and a heavily anti-incumbent cycle for governors (2002) — ever had this wide a difference in projected risk between the two parties. Instead, the typical ratio of vulnerable chambers between the parties has been close to even."

Both at the state level and at the national level, 2010 is shaping up to be "the worst election for Democrats since 1994," Tim Storey, an elections expert for the National Conference of State Legislatures, is quoted as saying.