Katie Couric's 'GMA' Co-Host Stint vs. Sarah Palin's Visit to 'Today': Tuesday's Showdown Has a Clear Winner NY Daily News

In the high-stakes morning ratings battle being waged this week between ABC and NBC, Tuesday’s second round went to NBC, the New York Daily News reports.

NBC’s “Today” averaged 5.497 million viewers Tuesday morning to 5.141 million for ABC’s “Good Morning America,” the story reports.

That makes NBC’s “Today” show two-for-two against ABC’s “GMA” with this week’s high-profile guest host, Katie Couric. As we reported previously, “Today” maintained its edge on Monday, 5.1 million to 4.8 million. Both shows improved on those numbers Tuesday.

“GMA” has three days of Couric left this week if it hopes to break “Today’s” unprecedented 850-week streak at No. 1. NBC seems determined to do whatever it takes to keep that streak alive, including arranging to have Sarah Palin sit in for Tuesday’s show.

In the most recent full week of ratings, "GMA" trailed today by only 137,000 viewers -- the closest margin in five years, the story notes.

Couric is filling in all this week for vacationing Robin Roberts. On the NBC side, the network followed Palin's Tuesday appearance with another big gun this morning, "American Idol" host Ryan Seacrest. Wednesday's viewer numbers will be available tomorrow.

Couric is a former regular on NBC's "Today."