This statistic, as presented, proves pretty much nothing.
Look, I'll cheerfully agree that our congresspeople are largely nicely-dressed whores who apparently will vote whichever way they're funded, but the statistics presented here are so confused as to be nearly meaningless.
The total given by those in favor may have been 40x that given against.
Then again, this could be (viewed objectively) simply a groundswell of opinion in favor.
I look at my senators (both D-MN):
Amy Klobuchar took $532,457 from those in favor, $16,298 from those opposed. ~30x as much.
Al Franken took $858,186:$11,400 almost 90x.
Two SOLID yes votes, as they vote mindless lockstep with their party.
Yet Jeff Flake (R-AZ), he received $588,966 $2,800 - a staggering 200x in favor, and voted "NO".
Mark Kirk (R-IL) $1,076,621to $28,200 or some 35x in favor, another "NO" vote.
So it doesn't seem that the wierdly-presented statistic of how much more one guy got from one side vs the other controls which way they voted.
I'd argue from opensecrets.org that the link between money and legislation is so obvious that it's hard to imagine that anyone could present it in a way that's NOT conclusive...like maplight managed to....