Michael J. Gaynor has two interesting pieces at MichNews.com
in which the charge of Heresey is laid out against Kerry. If you are a practicing Catholic, or are interested in learning about the seriousness of breaking with the teachings of the Catholic church, then these articles, particularly the second, are good to read.
... Mr. Kerry shamelessly wants to have it both ways: to be NARAL's champion and a practicing Catholic presenting himself to receive Communion as though he is in a state of grace and in full communion with the church and therefore fit to receive. He should be declared a heretic...
St. Matthew asked, “What is a man profited, if he shall gain the whole world and lose his soul.”
John Kerry, ..., wants to find out.
The case against Kerry is laid out here