In 2004, when the Red Sox swept the Cardinals in four games to win their first series since 1918, the average audience for Fox was 25.4 million viewers, according to Nielsen. At that time, it was the biggest audience for a World Series since the Atlanta Braves beat the Cleveland Indians in 1995.
Of course, there were some extenuating circumstances that helped boost the ratings for the 2004 World Series into the stratosphere. The Red Sox hadn't played in the Fall Classic since 1986. The team was also coming off a dramatic comeback win from three games down in the league championship series with the New York Yankees, which also generated a lot of interest in the team that this may finally be the year that the so-called "Curse of the Bambino" would be lifted.
When the Red Sox returned to the World Series in 2007 and swept the Colorado Rockies, the enthusiasm among viewers was not as big. Still, that series averaged 17.1 million viewers.
Because both the Red Sox and Cardinals have national followings, this year's World Series should have no problem topping last year's showdown between the San Francisco Giants and Detroit Tigers, which has the distinction of being the least-watched in history with an average audience of 12.7 million.
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