I usually get these things wrong (like when I predicted Rick Perry would be the next president), but just in case I get it right, I'm going to predict that, with Eric Cantor out, the unknown Democratic candidate, Jack Trammell, is going to be the next Representative from Virginia's 7th House District.
His campaign quickly pulled down the material he had on his website, no doubt the result of an instantaneous and massive Democratic machine that went into play immediately. But you can see that he beats his also unknown opponent on Rate My Professor.com.
For the record also, David Drury is disputing that Cantor lost because of his stance on immigration. After all, look at this flyer Cantor had out: