With just six weeks remaining in the current election cycle, GOP presidential candidate Mitt Romney’s opposition to the extension of wind energy tax credits and his ho-hum approach to renewable energy in his official energy policy are of understandable concern to advocates of blossoming renewable energy sources, including solar and wind.

Despite the solar industry’s significant interest in the outcome in the Presidential and Congressional elections, it is races deciding control of state legislatures that are arguably more important.

Since the Industrial Revolution, U.S. energy policy has been controlled at the state level. It was not until the 1930s that the federal government began major interventions into the energy marketplace, and even today the federal government takes a backseat to states on most energy-related issues, particularly concerning renewables. States lead the way -via Renewable Portfolio Standards and similar policies-in driving solar investment, technological progress, and cost reduction.

Last year, sunny Florida saw 23.5 megawatts of solar installed, putting the state around the middle of the pack in the nation in terms of installed solar capacity. Over the same time period, small, densely populated New Jersey saw over 300 megawatts of solar installed. Put another way, New Jersey – a state one-seventh the size of Florida – was installing more solar every month than Florida does in an entire year. New Jersey has some of the most robust solar goals and policies in the nation and Florida has nothing of the sort. That’s the power of state policy, and why state legislative elections are key for solar in 2012.

Solar learned this lesson the hard way in 2010, when the GOP captured more than 700 legislative seats from Democrats and took control of 20 legislative chambers. This massive shift in control in state legislatures was felt by solar in many ways, but most acutely in emerging solar markets like Pennsylvania, Ohio, and Texas, where efforts to grow renewable mandates were met with staunch opposition.

There is reason to be optimistic about solar’s prospects in state-level elections. The GOP’s historic 2010 gains now put them on defense in hundreds of state legislative districts which have traditionally elected Democrats. Despite what happens with the White House or Congress, this imbalance makes it difficult for Republicans to gain seats in some areas, but easy to lose them.

This pendulum-swinging creates opportunity for solar in key states. Arizona and Colorado, for example, were ranked third and fifth respectively in installed solar capacity last year. Both states, however, face a potential solar slowdown due largely to regulated utilities being at or near compliance with the state’s solar goals. Both legislatures have also been somewhat uninterested (if not outright antagonistic) regarding renewables. Positive progress will likely be made, however, with the 2012 elections. Democrats will likely make gains in the Arizona Senate – hopefully moderating the tone of the discussion with regard to renewables, and there is a decent chance that Democrats will recapture the GOP-controlled Colorado House. The New York Senate could also be taken by Democrats; further expanding solar’s opportunity in an important emerging market.

In fairness, the 2012 elections do not realistically present an opportunity to completely reverse the GOP’s 2010 gains or otherwise dramatically expand solar’s political base. Those with an interest in renewables should, however, shrug off the tendency to view elections through the prism of the top-ticket races, and focus energy on the critical races at the state level. Ultimately, they will play a key role in securing our clean energy future.

Postscript: As one with an interest in solar policy, I’m considering merely how the 2012 elections may impact the future political landscape. I’m not suggesting that a more-favorable political landscape is absolutely essential for solar’s future growth. In fact, as solar becomes more than cost-competitive with conventional energy sources, it’s easily argued that supportive policy is much less important in 2013 than it was in say, 2009-2010.