Despite its big, exclusive interview with Mitt Romney and Paul Ryan, the CBS newsmagazine “60 Minutes” couldn’t overtake its Olympic competition on NBC.

“60 Minutes” averaged 6.29 million viewers on Sunday, improving on its PGA Championship lead-in. The program averaged a 1.6 rating/4 share in the key adults 25-54 demo. By comparison, NBC’s Olympics wrap-up show averaged over 21 million viewers, while its coverage of the Closing Ceremonies averaged over 31 million viewers.

“60 Minutes” routinely averages well over 10 million viewers during the season, when it also has the benefit of an NFL lead-in, and is regularly a top 10 program on TV. With a last-minute interview giving CBS limited time to promote, and the Olympics Closing Ceremonies on NBC swallowing up every other TV show in its path, the program was unable to capitalize fully on its scoop, however.

Update: Also worth noting that “NBC Nightly News” actually averaged 10.37 million viewers, more than four million more than “60 Minutes.” Of course, NBC had the benefit of being the lead-in to the network’s Olympics coverage. “CBS Evening News” was preempted for the PGA Championship, and “ABC World News” drew 5.13 million viewers.