Ford Motor Co. won a heated contest among Detroit’s top automakers to get “Tonight” host Jimmy Fallon to buy one of their trucks, and may have done so through an ad pact with NBCUniversal.

Automakers including Ford, General Motors, Chrysler Group’s Ram Trucks and even Nissan have lit up Twitter since March 5 after Fallon revealed on “Tonight” that he intended to buy a truck. In the first segment of the March 28th episode of the program, Fallon revealed he had chosen a Ford F-150, and that the show would spend next week showing 10 Ford dealers from around the U.S. competing to sell him the vehicle by keeping their hands on a F-150 placed on the U.S.S. Intrepid in New York City.

The contest, called “Fingers on a 4X4,” was given an on-screen graphic festooned with a Ford logo, and the automaker made its victory known with tweets posted during “Tonight”:

The promotional deal suggests NBCUniversal isn’t content to let advertisers use Twitter to attach themselves to Fallon’s antics without buying spots during the show. In recent weeks. a number of sponsors have done just that: Ocean Spray, the consortium of cranberry growers, has been using Twitter to urge Fallon to give a nod to its “cranberry sauce singles,” an idea for a sandwich-fixing Fallon has brought up on ‘Tonight.” But the company at present has no intention to buy TV ads, said Thano Chaltas, Ocean Spray’s global chief marketing officer, in a recent interview.

Perhaps NBCU views the advertiser tweets as invitations to call and try to make a deal.

The appearance of the Ford ad during the program also suggests Fallon and his producers are open doing in-show commercials. The  technique that has gained more traction during latenight TV as so-called “commercial ratings,” or measures of TV viewers who actually watch the ads, have become the measure by which TV networks get paid by sponsors. Jimmy Kimmel on ABC, David Letterman on CBS and Conan O’Brien on TBS have all embraced the idea at different times in the recent past.