The weather is a great equalizer, but it doesn't affect everyone equally. A 2007 study revealed that foul weather depresses voter turnout, which heavily favors Republicans. With so many close elections today, any foul weather could result in a last-minute shift towards the GOP.

The United States is famous for its fickle weather and fickle politics. 537 votes out of more than 105 million wound up deciding the course of world history in the 2000 presidential election. With polls showing incredibly close elections today, every single vote will count and any factor that keeps people away from the polls could sway the results. While states across the country have implemented policies designed to suppress voter turnout, there are some things that are out of our control: the weather.

Three political scientists conducted a study a few years ago to determine if there was a link between depressed voter turnout and bad weather, and they found that bad weather (heavy rain or snow) has a significant effect on how many people head to the polls:

We find that, when compared to normal conditions, rain significantly reduces voter participation by a rate of just less than 1% per inch, while an inch of snowfall decreases turnout by almost .5% Poor weather is also shown to benefit the Republican party's vote share.

Basically, bad weather keeps people from turning out to vote. Who wants to trudge to their local church or elementary school in the pouring rain to stand in a long line around a bunch of drippy, humid people grumpily waiting to fill in a bubble next to the least worst choice? The answer is "only the most dedicated voters," and it seems that those dedicated voters trend conservative.

The study went on to show that there's a possible link in the weather conditions and the results of the 1960 and 2000 presidential elections, with dry weather in Illinois allowing John F. Kennedy to win the state by a few thousand votes, and rain in Florida possibly deterring just enough Democrats from voting to help George W. Bush limp through the gates of 1600 Pennsylvania Avenue.

In 2008, a major tornado outbreak occurred across parts of the southeastern United States on Super Tuesday, a date in February when two-dozen states held presidential primaries. CNN reports that some polling places in Tennessee and Arkansas had to close due to the threat of tornadoes. Neither state had results close enough that the weather had an effect on the outcome—Hillary Clinton won in Arkansas and Tennessee 73/27 and 54/40 over Barack Obama, respectively.

According to last night's Real Clear Politics polling averages, there are at least three Senate races where the leader—two Democrats and one independent— has a lead of one point or less: North Carolina (Hagan, +0.7%); New Hampshire (Shaheen, +0.8%); and Kansas (Orman, +1.0%). Recent polling averages show that Joni Ernst (R-IA) holds a 1.8% lead against her Democratic rival in the race for that state's open Senate seat.

Political analysts keep saying that these see-saw races will come down to which party is able to more effectively get out the vote today. In all of these races where a handful of votes could determine the outcome, any foul weather could benefit the Republican candidates.

The worst weather in the country today will occur from northern Texas through Arkansas, where rain and thunderstorms along an advancing cold front will produce several inches of rain across much of the state through tonight. Some areas could see between two and three inches of rain in the heaviest storms. Since most of the higher-ticket elections in the areas expecting heavy rain are foregone conclusions instead of nail-biters, it shouldn't have an impact on the outcome of any races.

The weather in the states with razor-thin margins in senatorial and gubernatorial races will be mostly dry, with the exception of some rain in Michigan (where incumbent GOP Governor Rick Snyder holds a slight lead over his Democratic challenger, Mark Schauer). Weather probably won't have an appreciable affect on election results tonight, but it's a real factor to keep in mind in future elections.

[Images: AP, WPC]

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