A San Francisco man tearfully admitted Thursday to making threatening phone calls to Speaker Nancy Pelosi (D-Calif.) over her support for the health care overhaul, the San Francisco Chronicle reported.

Gregory Lee Giusti, 49, pleaded guilty to one felony charge of impeding or retaliating against a Member of Congress. He struck a deal with prosecutors for a 21-month prison sentence. Sentencing is scheduled for Dec. 2.

Giusti admitted to making more than 30 phone calls between Feb. 6 and March 25. Investigators traced the calls to his computer.

Giusti spoke to Pelosi on March 25 and threatened to destroy her California home if she voted for the legislation, the Associated Press reported.

His criminal record includes a 1991 misdemeanor conviction for making harassing phone calls and a 2004 conviction for threatening to kill a train conductor, prosecutors told the Chronicle.