Despite recent cost increases, Dave Gilson isn't sure that the presidency is overpriced:
[C]ampaign costs have underperformed against real GDP growth: Since 1932, the GDP grew more than 1,700 percent, while real campaign costs grew around 1,360 percent.
Kevin Drum adds:
What's fascinating, to me, isn't that the costs of presidential campaigns have skyrocketed so much, but that they haven't. Until very, very recently, that is. From 1964 all the way through 2000, the cost of presidential campaigns was pretty stable, ranging around $300-600 million in inflation-adjusted terms. It was only in 2004 and 2008 that costs suddenly went through the roof.
Jonathan Bernstein believes that campaign finance regulations kept campaigns relatively cheap:
The real anomaly … is that the post-Watergate campaign finance regime held campaign costs artificially low. In the 1970s and into the 1980s, almost all presidential spending was done through one lump-sum public financing. In the 1990s, that was supplemented by the “soft” party money that was eliminated by McCain-Feingold restrictions, but that in turn spawned a variety of new spending mechanisms. The result is that spending, per eligible voter, has finally caught up to the levels of the past, or at least highly-contested campaigns of the past.