LOS ANGELES - Jimmy Fallon got a Donald Trump bump as the GOP presidential hopeful's appearance took "The Tonight Show" to its highest ratings for a Friday broadcast in 18 months.

NBC's "Tonight Show" brought in a 3.6 household rating/9 share in Nielsen's 56 overnight metered markets, which cover about 70% of U.S. TV households. In adults 18-49, Fallon averaged a 1.3/7. That was Fallon's highest mark for a Friday broadcast since Feb. 28, 2014, shortly after his debut at the "Tonight Show" desk.

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The week-one duel between Fallon and CBS' new "Late Show" host Stephen Colbert ended with "Late Show" drawing a 2.8 rating/7 share. That was its lowest household mark since it opened to a whopping 6.6 million viewers on Tuesday. But it was notable that the "Late Show" held steady Friday in its 18-49 average (0.8) of the past three nights despite the lure of Trump across the dial. And Friday's episode was up 47% from CBS' showing the same night last year.

Colbert's guests on Friday included Amy Schumer and Stephen King. Trump is set to visit "The Late Show" on Sept. 22.

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With the high level of scrutiny on the Fallon-Colbert competition, the biz will be eagerly awaiting the first time-shifted ratings for the new era of late-night. But that will require some patience. The live-plus-3 ratings for this past week are not expected to be released until late next week at the earliest because the L3 turnaround time for the late-night daypart is longer than it is for primetime ratings.