I think our 2008 Presidential candidates, thus far, have learned some very valuable lessons. Here's some of what I think they are, in no particular order:
Richardson - Having so much experience means that you are part of the problem.
Clinton - Having so much experience means that you are part of the problem.
Dodd - The mainstream counts.
Hunter - The mainstream counts.
Tommy Thompson - The mainstream counts.
Gravel - You can't anger people into voting for you.
Giuliani - You can't scare people into voting for you.
Kucinnich - Socialism is not popular.
Paul - Libertarianism is not popular.
Edwards - A one-issue candidate is not popular.
Huckabee - Humor will only get you so far.
Romney - Money will only get you so far.
Fred Thomspon - You have to act like you actually want to be President.
Bidon - Trash talking at the wrong time will get you trashed.
Gilgrist - You have to be in it to win it.
Obama - Being articulate and handsome has tremendous benefits.
McCain - Sympathy for great hardships you have endured will get you votes.