trying to learn about history of Presidential primaries

I was curious to read up on some history of previous presidential primaries and party national conventions to see how frequently candidates who start out scoring low in the polls (a year or two before the primaries), are able to do well in the primary elections. I didn't find exactly what I was looking for, but I did find some good wikipedia articles that have some of the background information that is helpful.

I'd recommend checking out the three links, http://en.wikipedia.org/wiki/Presidential_primary,
http://en.wikipedia.org/wiki/Republican_National_Conventions, and http://en.wikipedia.org/wiki/Democratic_National_Convention.