Electric Corp.'s finance arm to obtain millions of dollars in loans for Republic's used-car superstores, according to a person familiar with the negotiations.

Such financing would put in place the last element of billionaire H. Wayne Huizenga's strategy to duplicate in used cars his success in home video at Blockbuster Entertainment Co. Huizenga controls Republic, which has moved rapidly with acquisitions to establish a used-car supply and distribution network. Bermuda resident Michael DeGroote, is also a major investor in the company.

A partnership with GE Capital, the nation's largest finance company, would enable Republic to provide easier financing for customers of its AutoNation USA superstores, while pocketing some of the profits.

Used-car lenders "charge usurious rates. I've got to think that's got to be a target for Huizenga,''' said Stephen Weinress, director of research for L.H.

Friend Weinress.

Republic and GE Capital are in the second stage of negotiations and an agreement could be near, the person familiar with the situation said. But Republic also is talking with other companies, the person said.

GE Capital's chief rivals in the used-car market include AmeriCredit Corp. and Mercury Finance Co.

Republic and GE Capital declined to comment on the negotiations.

Republic has moved quickly into the $275 billion used-car business. In May, it purchased AutoNation USA, a company formed by Huizenga and two partners to develop used-car mega stores. A month later, Republic bought CarChoice Inc., which has two superstores.

Last month, Republic bought Bermuda-based ADT Ltd., the second-largest used-car auction house in the country, giving it an important supply source.

AutoNation will open its first store next month and plans to open 18 by the end of 1997, starting in Florida and Texas and expanding into Arizona, Nevada and Georgia. In 1998, the company plans to open one store every two weeks.

Republic says its sales should reach an annual rate of 600,000 vehicles by the end of next year.

The used-car business has exploded in recent years, thanks to the popularity of new-car leases. Sales of used cars through dealers has increased 35 percent since 1992 to 16 million vehicles, according to J.D. Power and Associates.

Huizenga has enlisted his protege from Blockbuster, Steven Berrard, and Jim Moran, a Toyota distributor, to help him in his used-cars venture. The trio formed AutoNation USA and sold it to Republic for $250 million.

What Republic investors got for their money was "a concept that had been developed for a year and a half, thousands of man- hours put into it ...

real estate being developed all over the country ... and a management team that is, in fact, among the finest management teams in the country,'' Tom Gruber, a spokesman for the company, said.

Republic paid another $95 million for CarChoice, and about $4 billion for ADT's stock and debt.

As Blockbuster's chief executive, Huizenga turned the unknown chain of 19 video stores into a household name with 4,700 outlets in nine years.

Huizenga is now chairman and chief executive of Fort Lauderdale, Florida-based Republic, a diversified company best known for its waste collection and disposal services. While its entrance into the used-car business might seem an unlikely fit, investors see the potential.