Pop quiz: Who's the governor of Georgia? It's a pretty important state, with a population greater than that of Virginia or New Jersey, to pick two others at random. Can't recall? Don't much care? You get my point—the fact that we momentarily care about who the governors of those other two states are is just an accident of the electoral calendar. It's perfectly fine to pay a lot of attention to the two states with gubernatorial elections in odd years just because there aren't many other elections happening. But come tomorrow, there's going to be a lot of media chin-scratching about What the 2013 Election Means. Was it a harbinger? A bellwether? A foreshadowing? An omen? Here's the answer: In the grand scheme of things, this election means ... almost nothing.
For example, did you know that in every election since 1978, the winner of the Virginia governor's race has been from the party that didn't control the White House? Fascinating! And yet Terry McAuliffe, a Democrat, is almost certainly going to win this time. Does that tell us something profound about the state of the parties in America today? No, it tells us that Virginia is a closely divided but nevertheless blue-leaning state, and the Republicans nominated a Tea Party candidate at a time when the Tea Party is in rather poor repute. You don't have to be Larry Sabato to figure that out.
And what about New Jersey? Does Chris Christie's impending win tell us that Christie could be president, what with the triumph of his (relative) moderation and straight-talking charisma? Not really. It tells us that the Democratic party nominated an unknown, and that Christie shrewdly insisted that the special election to fill Frank Lautenberg's Senate seat be held on October 16 and not three weeks later when they were having an election anyway, despite the considerable expense and hassle the extra election involved. If Cory Booker were on the ballot today, he'd probably get more votes than Christie, and that would temper all the speculation about how Christie will do at the next Iowa State Fair (insert your own food-on-a-stick joke here; they have 64 different options).
The point is, unless something truly spectacular occurred, the next year or two of American politics would play out exactly the same way no matter what happened in Virginia and New Jersey. You may have found one or both of them to be interesting races on their own terms. But if you're going to make an argument about what's going to happen in the future, you'll have to do better than citing the explanatory power of these elections.