Oprah Winfrey - the woman with the power to send authors to the top of the New York Times best-seller list - is planning to appeal to viewers tomorrow to back a crackdown on puppy mills in Pennsylvania.

Winfrey is expected to read excerpts from a letter Gov. Rendell sent to her last month seeking support for legislation to overhaul the state's dog law, according to participants in a Monday conference call with producers of The Oprah Show.

A spokesman for the show declined through e-mail to comment on the program for the live show.

Tomorrow's show follows an investigation by the show highlighting abuses in Lancaster County commercial kennels. The video showed sick dogs, dogs crammed into small cages, and dogs being mishandled by owners.

It generated one of the largest e-mail responses in the show's history, a spokesman said.

Two years ago, Rendell vowed to improve conditions in Pennsylvania's commercial breeding kennels. He wrote Winfrey after the show aired seeking help to counter "strong opponents in the breeding industry."