The National Jockey Club is suing its former partner in the ill-fated auto racing track built at Sportsman's Park for failing to pay over $35 million in debt from the project.The suit alleges prominent auto racing figure Chip Ganassi and his company, Ganassi Group LLC, was an equal partner with the NJC in financing the $70-million Chicago Motor Speedway. Charles Bidwill III, president of the NJC, said Ganassi believes he is not obligated to pay his share of the debt."Our partner reneged on commitments," Bidwill said in a prepared statement. "We invested $70 million in the Chicago Motor Speedway project as equal partners. The project didn't work out, and now Chip feels he is not obligated to share the responsibility. He wants us to bear remaining losses, including $35 million in bank debt. That's just not right."Sportsman's Park was closed in 2002, largely because of the failure of the speedway. The NJC continues to conduct a live race meeting at neighboring Hawthorne."We entered into this project with high hopes and expectations," Bidwill said. "It's disappointing Chip wanted an equal interest in profits, but refuses to bear the burden equally."