Greeks in American Politics

Sorry for the momentary hold on my posts of lately; this past week being formal RUSH week for UL's fraternities, coupled with an already intense semester, has been keeping me rather busy. So with fraternal organizations on my mind - greeks in particular - I stumbled across a piece on Google books (click the title of this blog to redirect to the corresponding article) which mentions the percent of Democrats/ Republicans/ Independents, who in addition to holding high political offices, are also greek. While the article pertains to the 70's and 80's, such information is still useful in raising a few questions - do greek organizations inspire potential leaders (early while in undergrad or graduate studies) to pursue a more professional career, namely one which involves high office? Also, additional information as it pertains to the percent of U.S. Presidents who were also greek would be similarly interesting.