The Dallas Cowboys got the nickname "America's Team" when Bob Ryan, now the Vice President and editor-in-chief of NFL Films, coined the phrase while preparing and editing the team’s 1978 season highlight film.
According to Yahoo Answers, Ryan came up with the name when watching different highlight films he noticed then "that wherever the Cowboys played, you saw people in the stands with Cowboys jerseys and hats and pennants. Plus, they were always the national game on television. He goes on to say, "I saw all these fans in away stadiums. Hey, they're the most popular team in the country. How can I use that? Why don't we call them "America's Team"?"
The name "America's Team," was then used again by an announcer during the first game of the 1979 season against the St. Louis Cardinals which Dallas won 22-21. The name stuck and has been used to refer to the Cowboys over the years, at least until now.
According to the 3rd annual NFL poll by Public Policy Polling the Dallas Cowboys are no longer America's favorite team, in fact the only thing the "Cowboys do win out for is America's least favorite team. 23% say the Cowboys are their least favorite team with no one else coming particularly close.
The question then is if the Cowboys are no longer America's team then who is? The is answer the Denver Broncos. According to the Poll 14% of Americans identify the Broncos as their favorite team followed by the Cowboys with 12%, the Packers with 11%, and the Bears with 10% as the top teams.
The reason for the rise in the popularity of the Denver Broncos is mainly due to Peyton Manning. In the poll he is taken a clear roll as the most popular quarterback in the NFL with twenty two percent of the votes.
If the poll shows anything it is how prone American's are to bandwagon jumping. In the last poll the Green Bay Packers were America's favorite team with 23% of the vote.
The complete poll results can be found at Public Policy Polling.