Evangelical Saddleback Church founder Rick Warren says that Christians have a disagreement with Mormonism because it "denies" certain fundamental Christian beliefs.

In an Easter Sunday interview on ABC, Jake Tapper noted that Mitt Romney, a member of the Church of Jesus Christ of Latter-Day Saints, was almost certain to be the Republican presidential nominee.

"Are Mormons Christians?" Tapper asked Warren.

"Well, the key sticking point for evangelicals and actually for many is the issue of the Trinity," the evangelical pastor explained. "Orthodox Christians, Catholic Christians, Protestant Christians, evangelical Christians and Pentecostal Christians all believe in the Trinity; that’s the historic doctrine of the church, that God is three-in-one. Not three gods; one God in Father, Son and Holy Spirit."

"Mormonism denies that. That’s a sticking point for a lot of Catholic Christians, evangelical Christians, Pentecostal Christians, because they don’t — they don’t believe that."

"Now they’ll use the same terminology, but they don’t believe in the historic doctrine of the Trinity," Warren added. "And people have tried to make it other issues. But that’s really one of the fundamental differences."

Throughout the primary season, Romney has had a problem getting support from evangelicals. He lost the evangelical vote by double digits in Tennessee, Michigan, Iowa, Ohio, Georgia and South Carolina.