An example is motivation for the Civil War. The baby Republican Party was founded on abolition and opposition to polygamy. That was what we now call the "base". The professional courthouse ex-Whig politicians were not abolitionist. Lincoln was a politician and did and said what politicians do.
He told the base what they wanted to hear. He told the ex-Whigs, who dominated Congress and the Northern legislatures what they wanted to hear. Historians are stupid if they take one politicially expedient comment of Lincoln and try to ascribe a "position" to it other than "political expediency". Lincoln lacked the "moral compass" of Bush and was more like LBJ.
As for the civil war, it should be noted that even before the formal actions of Lincoln and Congress, the Republican "base" was mobilizing themselves into militia. There were many (what would now be called fundamentalist) churches where every able bodied man (and boy) in the church volunteered for the militia with the motivation that is was the calling of God to reverse the sin of slavery. There were many Quakers, Mennonites and Amish who felt so strongly about abolition that they switched to the Free Methodist or Nazarene or Baptist church solely for that reason.
It was only after the abolitionist volunteers suffered such a heavy casualty rate (those ex-pacifists made lousy soldiers) and the ranks were decimated that Lincoln later imposed the draft and compulsory service on the Catholics and non-abolitionists who did not have a dog in that fight.