"...election data show that it is true that the candidate who spends more money in a campaign usually wins. But is money the cause of the victory?
It might seem logical to think so...But just because two things are correlated does not mean that one causes the other...
Now picture two candidates, one intrinsically appealing and the other not so. The appealing candidate raises much more money and wins easily. But was it the money that won him the votes, or was it his appeal that won the votes and the money?
That's a crucial question but a very hard one to answer. Voter appeal, after all, isn't easy to quantify. How can it be measured?
It can't, really - except in one special case. The key is to measure a candidate against . . . himself. That is, Candidate A today is likely to be similar to Candidate A two or four years hence. The same could be said for Candidate B. If only Candidate A ran against Candidate B in two consecutive elections but in each case spending different amounts of money. Then, with the candidates' appeal more or less constant, we could measure the money's impact.
As it turns out, the same two candidates run against each other in consecutive elections all the time - indeed, in nearly a thousand US congressional races since 1972. What do the numbers have to say about such cases?
Here's the surprise: the amount of money spent by the candidates hardly matters at all. A winning candidate can cut his spending in half and lose only 1 percent of the vote. Meanwhile, a losing candidate who doubles his spending can expect to shift the vote in his favor by only the same 1 percent. What really matters for a political candidate is not how much you spend; what matters is who you are." - Levitt & Dubner in Freakonomics.