Sen. Bernie Sanders Bernie SandersSirota reacts to report of harassment, doxing by Harris supporters Republicans not immune to the malady that hobbled Democrats The Hill's Morning Report - Sponsored by Facebook - Republicans lawmakers rebuke Trump on election MORE (I-Vt.) scored the first laugh of the fifth Democratic presidential debate on Wednesday by dredging up an old line: "I wrote the damn bill."

Sanders first made the quip — a reference to his signature "Medicare for All" legislation — during the second Democratic primary debate in July after one of his rivals, Rep. Tim Ryan Timothy (Tim) RyanNow's the time to make 'Social Emotional Learning' a national priority Mourners gather outside Supreme Court after passing of Ruth Bader Ginsburg Lincoln Project hits Trump for criticizing Goodyear, 'an American company' MORE (D-Ohio), suggested that the Vermont senator was unaware of what the single-payer health care proposal actually entailed.

Since then, Sanders has capitalized on that phrase, repeating it at times during public appearances and even selling campaign merchandise emblazoned with the slogan.

It resurfaced once again on Wednesday night after Sen. Elizabeth Warren (D-Mass.), Sanders's chief ideological rival in the presidential race, responded to a debate question about Medicare for All.

Once Warren finished her answer, the debate moderators posed a similar question to Sanders.

"Thank you. I wrote the damn bill," Sanders said as the crowd briefly erupted in laughter.