There have 11 different American League teams to win 59 out of 100 played. Only two years since 1903 has it not played, 1904 and 1994. The team with the most wins is the New York Yankees with 27 championships followed by the A's franchise with 9 (4 Oakland, 5 Philadelphia and 0 with Kansas City). Other teams include Boston, Baltimore, Detroit, KC Royals, Cleveland, Minnesota, ChiSox, Toronto, and Anaheim.
Update:
Through 2009, there have been 105 World Series played. The American League has won 62 and the National League has won 43. The A.L. has a winning percentage of .590 and the N.L has a winning percentage of .410.
Here is the breakdown of the 11 A.L teams. The current name of the franchise is used:
New York Yankees - 27
Boston Red Sox - 7
Detroit Tigers - 4
Baltimore Orioles - 3
Minnesota Twins - 3
Chicago White Sox - 3
Cleveland Indians - 2
Toronto Blue Jays - 2
A.L teams who have won the pennant, but never won a World Series are:
Milwaukee Brewers - 1 appearance
Tampa Bay Rays - 1 appearance
Texas Rangers - 1 appearance
A.L. teams who have never won a pennant are:
Seattle Mariners
In 2013, the Houston Astros moved from the National League to the American League, giving each league 15 teams for a total of 30 Major League Baseball clubs.
Click on the 'World Series Winners' link on this page to see a list of World Series winners from the first World Series played in 1903.
There are 14 teams in the American League. There are also 16 in the National League.
There were 30 teams in the MLB, 14 in the American League and 16 in the National League.
At the start of the 2012 MLB Season there are 30 teams, 16 in the national league and 14 in the american league. Starting 2013, both leagues will have 15 teams each with the Houston Astros being moved to the American League West division as required by Bud Selig.
Beginning with the 2013 Major League Baseball season, there will be 15 teams in the National League and 15 in the American League. A longtime imbalance between the two leagues is being solved by the transfer of the Houston Astros from the N.L. Central to the A.L. West.
30 teams
There are 14 teams in the American League of Major League Baseball.1414 teams
There are 14 teams in the American League. There are also 16 in the National League.
In the MLB there are 15 teams in the American League.
In 2010 there are 14 American League teams, and 16 National League teams.
There are 14 teams in the American league.
There are 16 teams in the American League 14 in the National League
There are 15 teams in the American League and 15 teams in the National League for a total of 30.
There were 30 teams in the MLB, 14 in the American League and 16 in the National League.
There are 30 teams. 16 in the National League and 14 in the American League.
There are 30 teams -- 16 in the National League and 14 in the American League.
There are 16 National League teams and 14 American League teams for a total of 30.
Currently (as of January 2014), there are 30 teams in Major League Baseball: 15 in the American League, plus 15 in the National League.