Those of us who report on state-level politics usually brag about how much better it is than following Congress. On our beat, after all, bills actually get passed and become law-unlike in D.C., where the Senate can't even vote for lack of cloture and the House just keeps reapproving the repeal of Obamacare in some endless Politico version of Groundhog Day. In state legislatures, deals get made, budgets get passed (even balanced, if that's your thing), and not every single issue is defined by a Democratic-Republican split.

Turns out we've been overstating things.

A new study shows that polarization-the ideological gulf between the average Republican and average Democrat-is growing in state legislatures. Political scientists Boris Shor (University of Chicago) and Nolan McCarty (Princeton University) combined survey results from the Project Vote Smart office-holder questionnaire with roll-call votes, comparing the average Republican and Democratic lawmakers in each state. (The data are available for anyone to play with.) Their findings tell us that state legislatures aren't quite as polarized as Congress, but they're moving in the same direction. What's even more interesting, though, is what polarization actually means-and who benefits from it.

Here's my take on what we can glean from the findings:

1. Most State Legislatures Are More Polarized than Congress

The gap between Democrats and Republicans in some state legislatures isn't just as big as in Congress-it's bigger. The states with the most polarization vary both in terms of geography and political persuasion. Among the five states with the biggest divide are Democratic-leaning states like California and Colorado, Republican-leaning states like Arizona, and middle-of-the-road states like Washington.

Boris Shor, The American Legislatures Project

In the past, party was not the only indicator of where state legislators fell on the ideological spectrum. Rural Democrats might overlap with urban Republicans on social issues, for instance, while urban Democrats and rural Republicans might agree on public-school funding. Those areas of agreement are increasingly few. In 2013, if a lawmaker supports affirmative action, odds are she also supports abortion rights and a progressive tax structure. "If you tell me one element of your beliefs, I can predict all the other elements of your beliefs," Shor says. "I'm gonna be right 90 percent of the time."

One reason for the shift: increasingly, national groups call the shots for Republican state lawmakers. Grover Norquist's no-new-taxes pledge, signed by 1,037 current state lawmakers, helped create a method for nationalizing state issues. Groups like the American Legislative Exchange Council (ALEC) have successfully pushed "model legislation" to Republican lawmakers around the country, accounting for the proliferation of voter ID laws and stand-your-ground laws, among others. Increasingly, big-money conservatives such as the Koch brothers support challenges to "moderate" Republican lawmakers on the state level to enforce ideological purity. The Republican State Leadership Committee (RSLC) spent around $30 million to elect GOP lawmakers in 2010 and another $25 million in 2012. (Democrats are playing catch-up, having spent nearly $11 million in 2010 and around $10 million in 2012.) In many state-level races, a few thousand dollars can make an enormous difference; the big national spenders help ensure that state lawmakers will be more in line with the national agenda.

Your donation keeps this site free and open for all to read. Give what you can... SUPPORT THE PROSPECT

2. Polarization Doesn't Always Mean What You Think

Polarization at the state level doesn't necessarily lead to congressional-style gridlock. For instance, California has by far the biggest ideological gap between state Democrats and state Republicans. But because Democrats thoroughly dominate the state, it hardly matters; they can pass bills to force fracking companies to be more transparent or help give flexibility to transgendered students. Similarly, in GOP-dominated states like Texas, Republicans have had little trouble passing a laundry list of conservative legislation.

A bigger surprise: Less-polarized states are not necessarily more moderate. Take Louisiana, which is one of the least polarized states according to the study-because its minority Democrats are so conservative themselves that the gap between the parties is very small. On the left, Massachusetts also has a small gap between the parties; the average Republican officeholder there is more liberal than the average Democrat in Louisiana.

The legislation passed in those states generally reflects what most voters want. That's not true in heavily polarized states with closer partisan divides. Wisconsin is among the states with an ideological gap bigger than Congress's. Even though the state votes blue in presidential races, Republican Governor Scott Walker, along with a GOP-controlled legislature, have successfully passed right-wing anti-union and voter ID laws. Similarly, Pennsylvania's Republican legislature passed voter ID and an extreme brand of welfare reform, even as Democrats won statewide on more moderate agendas. Michigan is another easy example, where GOP legislature of the historically pro-union state passed right-to-work laws designed to weaken the labor movement. It's no coincidence that all three states are Republican.

3. Polarization Helps Explain the Uptick in Conservative Legislation

It's easy to argue that Democrats and Republicans are equally responsible for the growing polarization. But who benefits the most from ideological gaps? The study doesn't attempt to answer this question, but it gives us tools to understand why Republicans have more successfully exploited polarized legislatures at the state level-just as they have in Congress.

There's no progressive equivalent to the power that right-wing groups like ALEC and Norquist's Americans for Tax Fairness have over Republican lawmakers. These groups have been notably active in creating a common conservative agenda across the states, promoting everything from lower taxes and budget cuts to anti-union measures and voter ID. It doesn't hurt that Republicans dominate significantly more capitols, thanks to their greater investment in state-level races. In 23 states, Republicans control the senate, house, and governor's office; by comparison, Democrats control all three in only 12 states.

Voters in the Republican-controlled states aren't necessarily extreme-but the legislation coming out of them often is. In North Carolina, Virginia, or Ohio, all battleground states at the presidential level and all more polarized than Congress, the legislatures have pushed far-right legislation. Ohio's GOP legislature passed anti-labor laws, only to see them repealed by voters through referenda. Virginia's pre-abortion sonogram bill prompted national outrage, while North Carolina's legislature, which first turned red in 2010, is slashing benefits for the needy and pushing to pass voter ID. While Democratic states like Maryland and California have pushed unabashedly liberal agendas, both states are also left-wing bastions. Across the Midwest, meanwhile, Republicans are passing extreme legislation in much more middle-of-the-road places.

Your donation keeps this site free and open for all to read. Give what you can... SUPPORT THE PROSPECT

That's possible, in part, because Republicans have another new advantage. Progressives and conservatives have "sorted" themselves geographically, so that Democrats tend to live in densely populated cities while Republicans control more suburban and rural areas. Since districts are drawn geographically, Democratic votes are too tightly packed and count for less.