Billy Graham has counseled every American president since Dwight Eisenhower. But the evangelist known for his globe-trotting crusades has no plans to mentor Barack Obama, though his son did say his father would like to meet the president-elect and pray with him.

Graham turned 90 on Friday. His son, the Rev. Franklin Graham, told The Associated Press that Billy Graham's mind remains sharp even as his body continues to fail.

Billy Graham still remains engaged in the planning and direction of the ministry he founded, but his days as a pastor to presidents have faded.

"My father feels like his time and day for that is over," Franklin Graham said. "But he would certainly like to meet (Obama) and pray with him."

About 160 of Billy Graham's family and friends celebrated his birthday Friday at his home in Montreat with fried chicken, barbecue and sweet tea. His ministry had received some 100,000 greetings, including a video from President Bush.

His health contrasts starkly with his days commanding a ministry that put him behind the pulpit to speak with 215 million people in more than 185 countries and placed him in the confidence of some of the world's most powerful people.

Billy Graham's views are still respected in White House circles. Republican presidential candidate John McCain called on Graham at his mountainside home during the campaign, and Obama tried to meet him but was unable to due to the preacher's poor health.

Though never partisan in his preaching, Billy Graham is a registered Democrat.

His son expressed concern about Obama's views on abortion and gay marriage — an issue Franklin Graham raised in a meeting with the Illinois senator — saying that he and is father are conservatives who believe the Bible speaks clearly on those issues.

"President-elect Obama heard our position," said Franklin Graham, who now heads the Charlotte-based Billy Graham Evangelistic Association. "And I told him that this was very difficult for us and hard for us. It's a moral issue that we just can't back down on."

Obama favors abortion rights, and does not support a constitutional amendment to ban gay marriage. He supports civil unions and believes states should decide their own laws about marriage.

Meanwhile, Billy Graham's health remains a concern among family and friends, who note he still struggles with the loss of his wife, Ruth, who died last year.

He was hospitalized last year for nearly two weeks after experiencing intestinal bleeding, and he has also had prostate cancer. Earlier this year, he had elective surgery to update a shunt that controls excess fluid on his brain. The shunt was first installed in 2000 and drains fluid from through a small tube, relieving excess pressure that can cause symptoms similar to Parkinson's disease.

"He could catch a cold and his life could come to an end," Franklin Graham said. "At his age, any little thing could be a serious event. We realize that."

Despite his limitations he still has one thing: a booming voice.

This weekend, that voice will once again cross borders when a message dubbed in Portuguese will be broadcast in Brazil in an effort to bring some 1 million new believers into the fold.

And privately, he has been working on a book about aging, trying to put his late-life lessons into context for those soon to follow him.

"He's always been ready to die," Franklin Graham said. "But nobody's prepared him for getting old."