WASHINGTON — Republican vice presidential candidate Paul Ryan on Thursday denied for a second time that he ever lobbied the government for stimulus money, even though he sent letters —with his signature — to the Energy Department and Labor Department asking for millions of the program’s dollars on behalf of two companies in Wisconsin.

Ryan’s new denial in an interview with Cincinnati’s WCPO-TV contradicts letters that Ryan wrote in 2009 to Energy Secretary Steven Chu and Labor Secretary Hilda Solis seeking stimulus grant money for two Wisconsin energy conservation companies. One of them, the nonprofit Wisconsin Energy Conservation Corp., later received $20.3 million from the Energy Department to help homes and businesses improve energy efficiency, according to federal records.

The congressman’s denial comes as new audio surfaced of Ryan telling Boston’s WBZ Radio two years ago that he “did not ask for stimulus money,” in response to a caller’s question about the recovery program. “I’m not one who votes for something and then writes to the government to ask them to send us money,” Ryan said. The exchange was first reported Thursday by The Boston Globe.

But a year earlier, Ryan asked Chu to set aside funds for the Wisconsin Energy Conservation Corp. Ryan said the stimulus cash would help his state create thousands of new jobs.