Back then, there wasn't an obsession about republicans and democrats. Most agreed that we all wanted the same things for America, but had different ways of achieving it. LBJ and the Great Society changed that, and the extremists came out of the woodwork, particularly concerning Vietnam. The division widened ever since.
Of course, people like Pelosi and Reid took the division to an all new level. They are extremists who should never be in leadership positions, but can look you in the eye, and lie their arses off. That is not differences, but pure evil.