Stephen Colbert, right, chats with Republican presidential candidate Jeb Bush during the debut episode of "The Late Show With Stephen Colbert," Tuesday night, Sept. 8, 2015. Jeffrey R. Staab/CBS

CBS and Stephen Colbert pulled out all the promotional stops in the weeks running up to the launch of “The Late Show With Stephen Colbert” Tuesday, and the push was good enough to help Colbert dominate the competition. According to preliminary Nielsen estimates, Colbert drew a household rating of 4.9, more than twice the audience share earned by NBC "Tonight Show" host Jimmy Fallon (2.4), and far ahead of Jimmy Kimmel (1.4), James Corden (1.3), Seth Meyers (1.1) and Carson Daly (0.7).

Colbert drew an audience of about 6 million viewers, an impressive draw for a late-night talk show. But he didn’t hold a candle to the ratings bonanza his buddy Fallon delivered last year when he took over as "Tonight Show" host. Fallon, who’d spent the previous few years building a passionate fanbase hosting NBC's “Late Night” while Jay Leno played out the final years of his contract, drew 11.3 million people, nearly three times the audience that Leno typically delivered and 80 percent more than Kimmel and David Letterman (Colbert's predecessor) combined.

That Fallon debut turned out to be the second-largest audience for a “Tonight Show” episode since 2009, behind only Leno’s final episode of “Tonight” (14.6 million in February).

The huge gap between those two debuts should be taken with a grain of salt. Fallon got to ride into his star-studded debut on the coattails of the 2014 Winter Olympics, a ratings monster that performed quite strongly. By contrast, Colbert had to rely on regular 11 p.m. local news shows, which have an audience that's much smaller, and much older, than the Olympics typically draws. It also aired in the summer, when ratings of network television are typically lower than during the winter.