Many of those running in Tuesday's elections are running for state offices. As federal legislators sit around twiddling their thumbs state legislators are busy making tons of sausage. States have enacted their own individual legislations on immigration, guns, women's rights, gay marriage, the environment, marijuana use, voter ID and tons more.
While major media is all sweaty over who gets control of the Senate in Washington next year, states are exercising their rights over that of federal law. Therefore state & local laws are far more likely to impact people directly
For example. In Philadelphia you can be caught with a small amount of pot for personal consumption and only receive a fine. Same goes in many other cities and states where in one place someone could get fined, while in another locked up for years. Unless someone is a dealer and attracts the attention of federal agents they are more prone to be searched by state and local authorities on patrol then federal agents..
That's why this election is just as important as the local elections or the national elections for President (if not more so). Voting to send a candidate down to the swamp Washington has become (where little is getting done) has lesser importance then whom voters choose in the areas in which they reside.