Oct 20 (Reuters) - The television audience for the final presidential debate between Democrat Hillary Clinton and Republican Donald Trump was larger than for their second encounter, but below their record-setting first debate, according to early data cited by U.S. media on Thursday.

Variety said that preliminary Nielsen estimates showed Wednesday's debate getting a 39.7 overnight household rating in the nation's biggest cities. The first Clinton-Trump face off in September scored a 46.2 overnight rating that translated into a total TV audience of 84 million.

Final figures across all U.S. networks that carried the debate live will be released by Nielsen later on Thursday.

(Reporting by Jill Serjeant) ((jill.serjeant1@thomsonreuters.com; 646 223 5968;))