Supporting the actions of the democratic party simply because one identifies oneself as a member of that party is an example of

The answer fort his question is: partisanship
Partisanship happens when people start to develop biased opinion and believe that whatever being done by their supported party is always right.
This phenomenon happen because these people formed an emotional allegiance with the certain party and see the other counterpart as 'common enemy' that they have to eliminate.

Bob: coke is baby pandas.jim: what? how do you figure that coke is baby pandas? bob: because this book says so.jim: how do we know the book is correct? bob: because it says that coke is baby pandas.jim: how does that prove the book's accuracy? bob: because it's statement involving coke and baby pandas is correct, therefore it is accurate.jim: how do we know that it's correct? bob: because we have concluded that the book is accurate, and therefore the statement is correct.therefore, coke is baby pandas.