The following article relates Kerry's experiences while attending boarding school at St Paul's in New Hampshire. The beginning discusses how many of his classmates have worked for those running against him in various races.
I found it enlightening and interesting. Even among the well to do there is classism of sorts.
http://www.keepmedia.com/pubs/NewRepublic/2004/04/12/410213"Kerry certainly dressed the preppy part. But there were obvious ways in which he could not keep up. While his classmates summered in Europe (or even took private jets to the Continent for long weekends), Kerry spent his breaks working as a Teamster in Somerville, Massachusetts, for the First National Stores, loading food onto trucks. He frequently borrowed money from friends. And, if his relative poverty weren't apparent enough, Kerry always had richer classmates issuing reminders of their bigger bank accounts.
snip....One of Kerry's poorer classmates had carefully compiled a record collection that was his proudest possession--and everyone in the school knew it. But a rich classmate couldn't stomach the satisfaction felt by Kerry's friend, so he ventured into Concord and bought out the record store. According to Barbiero, Kerry empathized with the collector. "John was upset about this and thought it was a nasty thing to do."
snip
How then to explain the preppy hatred for Kerry? In part, the answer has to do with the changing times. During the late '50s and early '60s, the blue bloods' grip on power was coming to an end. For a long time, St. Paul's and the other New England boarding schools were the Ivy League's main pipeline. Every year, St. Paul's sent about half its class to Harvard and Yale. By the end of the '60s, with the introduction of the SAT and a new democratic spirit in the admissions offices, that era of dominance had ended. As William F. Buckley lamented in a 1968 Atlantic piece, "You will laugh, but it is true that a Mexican-American from El Paso High with identical scores on the achievement tests, and identically ardent recommendations from the headmaster, has a better chance of being admitted to Yale than Jonathan Edwards the Sixteenth from Saint Paul's School." With his hardworking style, Kerry represented the new meritocratic ethic, where success wouldn't depend on blood and charm but the earnest accumulation of achievements. Of course, Kerry may simply not have been very likeable. But, at least in part, Kerry was hated because he embodied the emerging reality that the old insular world could no longer afford to be so insular.