WASHINGTON — Long one of President Trump’s most ardent defenders, the evangelist Franklin Graham voiced strenuous dissent this week about the practice of separating families at the border, even calling it “disgraceful.” His comments, along with other criticism from the evangelical community, raised the possibility that the president’s support from conservative Christians might erode as outrage mounted over the Trump administration’s “zero-tolerance” immigration policy.

But if evangelical leaders were pained by the sight of children being taken from their parents, they did not directly fault Mr. Trump.

Instead, many blamed Congress and past administrations, Republican and Democrat, and emphasized that Mr. Trump called family separation “horrible” in a tweet and that he wanted a legislative fix for immigration. And though it is too early to know the electoral consequences of the policy, few conservative Christian political leaders have been concerned that Mr. Trump will lose support among their ranks, which represent one of his most important voting blocs.

“This is not the administration’s fault,” Mr. Graham said in an interview on Monday, while reiterating his stance against family separation. “I don’t point the finger at Trump.’’