Experience and due diligence

We are told that experience counts but we know that Senators have rarely been elected to the Presidency. It's all that experience.

In 2008, the major presidential candidates are all from the Senate. Here is a service from Cato that scores Senators and Representatives in terms of how they voted on subsidies and trade barriers.

Rational voters may under-invest in due diligence but when modern communications lower its cost, we have to appreciate progress.