From September 24, 1916
Why Are You a Democrat or a Republican?: We Are Fortunate in Having a Permanent Election issue on Which We May Take Sides Without Impairing Our Loyalty (PDF)
Columbia Professor Brander Matthews was able to write the following in 1916, of American political parties:
Now, it is impossible to declare abstractly that either party is absolutely right… Each can respect the other and respect the other’s point of view. Both can agree to disagree without being moved to hatred or to contempt. And here is where we Americans have our inexpugnable advantage over the voters of most other countries. Here also is where the American citizen who has had the benefit of an education which has liberated his mind, which has freed him from the unnecessary prejudices, and which has trained him to try to understand (and even to esteem) the opinions he does not share.
This year, 58 percent of Republicans have “very unfavorable” views of the Democratic Party, up from 21 percent in 1994 — while 55 percent of Democrats have “very unfavorable” views of the Republican Party, up from 17 percent in 1994. That’s according to survey data from the Pew Research Center.