Sharply escalating the war of words over the National Day of Prayer, the Rev. Franklin Graham predicted Thursday that "millions of evangelical Christians" who voted for President Obama in 2008 would reject him because of the administration's controversial policies.

That followed Graham's remarks this week in an exclusive Newsmax interview that revoking his invitation to speak at the Pentagon's National Day of Prayer event represented a "slap at all evangelical Christians."

Editor’s Note: See “Franklin Graham: Obama 'Giving Islam a Pass,' Warns of Persecution.”

Pentagon officials had declared that it would be "inappropriate" for Graham to speak at the event, because of remarks he made in the aftermath of 9/11 that Islamic teachings had made that faith "a very evil and wicked religion."

Despite the ban, the Samaritan's Purse charity founder and son of world-famous evangelist the Rev. Billy Graham pulled into the Pentagon parking lot just after 8 a.m. Eastern time.

Accompanied by a group of close associates and friends, Graham strode to a sidewalk outside the Pentagon. There the group stood in a circle and with heads bowed, prayed for God's protection over the nation's armed services personnel and their families.

For Graham, the prayer was personal. His son Edward is a West Point graduate and Army Ranger now serving his fourth tour of duty in the Middle East, after recovering from shrapnel wounds sustained in 2007.

While Graham and the National Day of Prayer Task Force he leads as honorary chairman were excommunicated from the Pentagon, Andrea Stone of AOL News reported those invited to attend the Pentagon ceremony included Jewish, Catholic, and Muslim chaplains. The service was led by the head of the Armed Forces Chaplain Board, a Protestant.

Earlier Thursday, in a CBN News interview with White House correspondent David Brody, Graham said: "There were millions of evangelical Christians that voted for Barack Obama in the last election. I don't think they'll be at the table next time. I think they've seen things from this administration that concern them, that worry them."

Mark DeMoss, the Atlanta-based public relations expert and founder of The DeMoss Group who is traveling with Franklin Graham, told Newsmax on Thursday that no one from the administration ever followed up on the president's commitment to look into the Pentagon's revocation of the Graham speaking engagement.

"Franklin has not heard from the White House since he spoke with the president April 25 at his father's home," DeMoss informed Newsmax via e-mail.

After that meeting involving President Obama, Billy Graham, and Franklin Graham, the younger Graham warned the president that anti-Christian activists were trying to drive all vestiges of the Christian faith out of the U.S. military.

The president told Graham he had become aware of the controversy only recently and would "look into it." But there was no further communication.

Christian leaders and conservative politicians around the country came to Franklin Graham's defense Thursday.

"I can't tell you how much I appreciate this man, because he has been on the front lines," Focus on the Family Founder James Dobson told CBN News. "He's taken the heat, and he's done it with grace … he takes an opportunity like this and he goes straight to the gospel."

"We are extremely disappointed that the Pentagon would withdraw his invitation," Focus on the Family Vice President Tom Minnery tells Newsmax.

"Particularly with the tremendous heritage of Christian outreach that Franklin and his father have earned over the years, for the Pentagon to turn against that symbol of American Christianity is shocking."

Minnery later modified his statement to say he was more disappointed than shocked, because it had been evident for some time that Pentagon might opt to rescind Graham's invitation.

"Who would have thought prayer would be controversial?" 700 Club founder Pat Robertson said on his Thursday broadcast. "Well, in the United States, with a bunch of left wingers, it gets to be a controversy."

Former Christian Coalition leader Ralph Reed told Newsmax, "The disinviting of Franklin Graham from the national day of prayer event at the Pentagon is just the latest example of the Obama administration being out of touch with the values of the American people."

Reed concurred with Graham's prediction the administration's perceived cold shoulder to Christians — in April 2009 it asked that a crucifix and Christian symbol be covered up before the President spoke at Georgetown University, and recently supported healthcare reform legislation that indirectly authorizes the expenditure of public funds to pay for abortion — will have consequences at the ballot box.

"It is a slap in the face not only to people of faith, but to all Americans who honor the Judeo-Christian values upon which our nation was founded," Reed tells Newsmax. "It is just the latest insult that is driving a backlash at the polls in November."

During his remarks at the National Day of Prayer event, GOP Rep. Mike Pence, the chairman of the House Republican Conference, appeared to allude to the growing Christian sentiment that the faith is under assault by secular forces.

"Sadly, voluntary prayer has been under attack of late, driven from our public schools and our graduation ceremonies by activist courts. And just last month, a federal court declared this National Day of Prayer to be unconstitutional. That ruling ignored our history and our traditions and should be overturned," Pence said in prepared remarks circulated to the media.

“During these days of challenge for American families at home and abroad, on this National Day of Prayer, let it be said now more than ever: we're a nation of prayer," he added.

On Wednesday, Pence and 35 of his colleagues sent a letter to Secretary of Defense Robert Gates urging the military to re-issue a last-minute invitation to Graham to attend the event.

During Graham's exclusive interview with Newsmax on Monday, he made it clear that he held the administration responsible for the Pentagon snub.

"But I certainly believe that it was people in his administration that said no," Graham said. "I don't think the Pentagon would say no on an invitation like this without consulting the White House."

Brody remarked that Franklin Graham, who tends to avoid political skirmishes, recently has been encouraging Christians to register, vote, and participate in the political process in order to protect the country and their cherished values.

"This is pretty blunt political talk from Franklin Graham, who typically does not get involved in any of this," Brody observed.

The federal government has called for a National Day of Prayer in May for nearly 50 years. In April, U.S. District Judge Barbara Crabb of Wisconsin ruled that holding a National Day of Prayer is unconstitutional, maintaining it violates the First Amendment's prohibition against the establishment of a religion by the federal government. The ruling stemmed from a lawsuit filed in 2008 by a group of atheists and agnostics.

The Justice Department has announced it will appeal Crabb's ruling, and Graham has praised that decision. President Obama signed a proclamation recognizing this year's Day of Prayer event. He did not, however, hold a ceremony in the White House recognizing the importance of prayer in American life as President Bush did in prior years during his term.

In his remarks to Brody, Graham emphasized, as he had in his interview with Newsmax, that he loves the Muslim people. But he continued to take shots at the administration's move to distance itself from leaders who espouse the basic biblical tenets of the Christian faith.

"I think it is a put down, because it seems to be that Islam gets a pass, that a couple of Muslims can complain about a Christian event at the Pentagon, when there's been Christian events for years at the Pentagon," Graham told CBN News.

"(Muslims) can have Ramadan, they have their prayer services there, I don't complain, I'm happy for them to do that," he continued. "But for them to complain because I don't believe as they believe and I don't worship the same God that they worship… I worship a different God than they worship. But we love them."

Minnery told Newsmax that he's disappointed to see how Graham and the believers he represents have been treated.

"The issue of prayer transcends politics," Minnery says. "And it seems that the president, by condoning the Pentagon's choice, has injected politics into it."