A few years after graduating from law school, David E. Kendall wrote an article, entitled "How to Keep Your Client Alive," in which he offered advice based on his extensive experience defending inmates on death row. Now Mr. Kendall, a lawyer little known outside bar circles, is working for the political survival of Bill and Hillary Clinton.

Since last summer, he has been the Clintons' personal lawyer. His role became public only last month, after it was disclosed that the Clintons had used him to negotiate the terms of a Justice Department subpoena for the business records of their real estate investments in the Whitewater Development Corporation. The Clintons had a partnership in the company with James B. McDougal, the proprietor of an Arkansas savings and loan institution that is now closed.

Almost like a mantra, friends and partners describe the 49-year-old Mr. Kendall as an "earnest Midwesterner," a soft-spoken Indianian with a rabid appetite for movies (high-quality and low-), literature (high-brow and junk) and history (American and European). His passion for social causes goes back at least to 1964, when he was arrested in Mississippi while registering black voters. Specialist on Death Penalty

To those who do not know Mr. Kendall well, he seemed an unusual choice for the President and his wife. Mr. Kendall's legal specialty over the last two decades has been death penalty and libel cases. His clients have ranged from Playboy magazine and the National Enquirer to William F. Buckley Jr., the conservative columnist and author, and John A. Spenkelink, the first convict executed against his will since 1977, when executions were resumed in the United States after a 10-year hiatus.