Current projections are that the Democrats will retain control of the Senate by a narrow margin. But that could change, particularly if Romney continues to surge and carry GOP Senate candidates along with him. Energy and environmental policy are areas where this really matters. The House of Representatives has passed numerous bills relating to energy and environmental issue over the past two years. These bills have died in the Senate, but that could change with a new Senate.

Republicans in almost all of these races are outspoken opponents of environmental regulation.  Richard Mourdock in Indiana has said that climate change is a hoax and talks about the “jackboot” of environmental regulation. Danny Rehberg in Montana has a lifetime rating of 6% from the League of Conservation Voters, while Dean Heller in Nevada has a 14% lifetime rating. This puts them well to the right of Paul Ryan, who has lifetime rating of 20% from the organization. George Allen in Virginia and Linda McMahon in Connecticut have also emphasized their hostility to environmental regulation. Scott Brown in Massachusetts is closer to Paul Ryan than to the most extreme Republicans, although that’s still the lowest score in his state’s congressional delegation.

The Democrats are more of a mixed bag.  Most are staunch advocates of environmental regulation. Chris Murphy in Connecticut, Jon Tester in Nevada, Tim Kaine in Virginia, and Tammy Baldwin in Wisconsin all emphasize their strong support for environmental protection. But some other Democrats emphasize their support for coal, gas, and oil, despite environmental concerns.  This group includes Joe Donnelly in Indiana, Claire McCaskill in Missouri, and Shelley Berkley in Nevada.  The one point where the Democrats seem to be unanimous is their support for renewable energy.

The contrasts are especially sharp in some of the races.  In Connecticut, Montana, and Virginia, the candidates are miles apart on environmental issues. In Wisconsin, Tammy Baldwin supports cap-and-trade, while Tommy Thompson hasn’t even mentioned climate change in the past five years.

Even apart from who controls the Senate, the outcomes of these individual Senate races really matter. The Senate’s size and procedural rules make individual senators much more influential than individual members of the House of Representatives. A single senator can put a hold on a presidential appointment to the executive branch or the judiciary. Moreover, an individual senator can carve out a niche as a leader on particular issues.  Democrats Chris Murphy (Conn.) and Tammy Baldwin (Wisc.) might well become leading champions of the environment, while Republicans Mourdock (Ind.) seems likely to lead the crusade for more fossil fuels regardless of environmental impacts.

In the past two years, the Republican majority in the House of Representatives has embarked on a major campaign to roll back environmental regulations.  It has voted repeatedly to overturn EPA air pollution regulations, to open more areas to oil drilling, and to eliminate restrictions on fossil fuels. Depending on how the presidential race turns out, they may have a firm ally in the White House.  That makes these Senate races even more crucial.