Mr. Chatwal pleaded guilty in Federal District Court in Brooklyn on Thursday to skirting federal campaign contribution laws and witness tampering, admitting that he had funneled more than $180,000 in illegal contributions between 2007 and 2011 to three federal candidates — identified by a person with knowledge of the investigation as Mrs. Clinton, Senator Christopher J. Dodd of Connecticut and Representative Kendrick B. Meek of Florida.

Mr. Chatwal owns the Chatwal and the Dream hotels and the Bombay Palace restaurant chain. He has long been shadowed by financial and legal problems in both the United States and India, filing for bankruptcy twice, facing allegations of bank fraud and owing millions in back taxes.

Now, Mr. Chatwal, 70, faces up to 25 years in prison. It is not hard to discern Mr. Chatwal’s motivation for his scheme, according to information filed by federal prosecutors. He described the importance of the donations to a government informant in a recorded conversation:

“Without that nobody will even talk to you. When they are in need of money,” he said, “the money you give, then they are always for you. That’s the only way to buy them.”

The Chatwal family has had a colorful history. Mr. Chatwal’s other son, Vikram, is a night-life fixture whose corporate website describes him as a “man-about-town” who has “friendships with some of Hollywood’s most influential stars,” has dated the models Gisele Bündchen and Esther Cañadas, and is a friend of the rapper Sean Combs and the actress Lindsay Lohan. He was arrested last April after trying to board a flight while carrying cocaine, marijuana and prescription pills, and has had several stints in rehabilitation.

The elder Chatwal’s realm was politics: He had a private dinner with Ms. Clinton when she was visiting India and was a regular at state dinners at the White House under three different presidents — Mr. Clinton, George W. Bush and Barack Obama.