Below the net wins over the series is shown. The higher on the y axis the more Republican wins and the lower on the y axis the more Democrat wins. From this graph it is fairly obvious that each party has had long winning streaks. The gray dots represent years when the game was not held or I could not find any information about the game. In 1935, 1937, 1938, 1939, and 1941, games were held between members of congress and the press.
The following graph displays the points scored by each team over time. In the early years of the series, the games had much higher total scores than more recent years.
A histogram was formed to understand the distribution of point differences. The Democrats have some extremely large wins with three wins over 20 points and the Republicans have none. Another interesting finding is that only one game ended in a tie. This is surprising because the charity event does not have overtime so it is logical to think out of the 81 games played more than one would end in a tie.
Ironically, RFK Stadium, named after the famous Democratic U.S. Senator, has given Republicans a strong home-field-advantage. Republicans have won 13 out of the 14 games played at the stadium. Democrats have seen similar success at Nationals Park; winning 7 out of the 9 games.
Notes:
- The data came from https://en.wikipedia.org/wiki/Congressional_Baseball_Game#Game_results
- Some of the stadiums were renamed over the years and the original data set contained both names. For the analysis, the same stadiums were combined with the most recent name.