They didn't write them. People who are articulate and entertaining wrote them. Not the networks, apparently, who seem to believe that politics equals low ratings. So does a TV ad. An e-mail, in contrast, costs a few cents.
Candidates conserve money and therefore have to raise less of it from insidious special interests.
Perhaps John McCain didn't go far enough. Of course, if McCain were still in the race, the prospect of a campaign where you didn't have to actually see and hear the candidates wouldn't be nearly as appealing. Why Bush has plenty of time to reposition himself. The case for selling the Lincoln Bedroom. Giuliani vs. the non-profits.