Ron Paul 2008 is driven mainly by small donations! He relied more on small contributions more than "top-tier" candidates in (these are Q2 figures): (http://www.usaelectionpolls.com/2008/articles/ron-paul-small-donors-love-him.html):
Candidate | $200 or less | $200 to $1000 | $1000 to $2300 |
Paul | 47% | 36% | 18% |