Two-by-two, lawmakers left the church where the Rev. Martin Luther King Jr. (search) once preached and walked to a black granite civil rights memorial bearing the names of those killed in the 1960s struggle for equality.

Led by Senate Majority Leader Bill Frist (search), R-Tenn., and one-time King aide John Lewis, they clasped hands, closed their eyes and sang "We Shall Overcome."

Frist called the visit a sacred pilgrimage. It also was one in a series of "Kodak moments" the Tennessee transplant surgeon has strung together as he positions himself for what colleagues say will be a run for the White House in 2008.

"This is the kind of preliminary public relations that you couldn't buy for any money," said David Bositis, a political analyst with the Joint Center for Political and Economic Studies, a black think tank in Washington.

Frist, who organized the three-day tour of civil rights sites in the South last weekend, bristles at that suggestion.

"Every move I make, people are going to say there's some political motivation," he complained recently.

Frist heard such speculation in Washington when he invited his former patients to the Capitol for a fall reunion, and he heard it in Iowa and New Hampshire when he showed up for the recent political contests there. Amid the Republican chatter about President Bush possibly replacing Vice President Dick Cheney, Frist's name has come up as a potential No. 2.

In the past six years, Frist has shown an ability to be in the right place at the right time, the physician's voice of calm in the midst of panic, whether over a political upheaval in the Senate or chemical-biological attacks on the Capitol.

The speculation about 2008 is partly fueled by Frist's statement that he won't run for re-election in 2006. He hasn't said what he'll do, but political observers say that would be the time to launch a presidential bid.

"There's a lot of talk about it. He's very popular with Republicans around the country," GOP strategist Charles Black said.

Many of Frist's Senate colleagues privately say they believe Frist will run, and Sen. Jim Bunning, R-Ky., recently told reporters he's fairly sure of it. "Just watch him," said Bunning, who called Frist's rapid ascension to the majority leader post breathtaking.

Frist leapfrogged into the Senate's top job 14 months ago after former Majority Leader Trent Lott was criticized for praising the late Sen. Strom Thurmond's 1948 segregationist run for president. With backing from the White House, Frist won what quickly became a contest of one.

A month earlier, Frist was given much of the credit for recruiting GOP candidates and raising enough money for the Republican to seize the Senate majority from Democrats.

Frist became a regular presence on TV reassuring an anxious public about anthrax-laced letters sent to Congress and media outlets in 2001. Lott made Frist the Senate spokesman on the attacks. Asked about giving his successor the high-profile assignment, Lott recently said, "Yeah, it's funny how you do those things."

Others say Frist's calming presence made him stand apart during the anthrax attacks and more recently when the poison ricin was found in his office.

"Health care is going to be hot, and Bill Frist knows how to handle health care better than anyone, and more importantly he knows how to communicate it," said Republican pollster Frank Luntz.

Frist's biggest accomplishment as majority leader has been winning passage of a long-sought prescription drug benefit to Medicare. The legislation was praised by the AARP but attacked by critics as a sellout to insurance and drug companies.

Democrats have long argued that Frist is too cozy with the health care industry.

Frist reports having blind trusts worth up to $31 million — wealth generated by his family's original ownership of the hospital chain HCA. While there is little debate Frist sounds knowledgeable when talking about health care, he is less adept when the topic strays to other issues.

During a visit to a black church in Nashville, his message was long on his own accomplishments but short on emotions. Lewis gives Frist the benefit of the doubt, saying the typically nonplussed majority leader started to cry while looking at a civil rights exhibit in Nashville. "I could see that he was deeply moved and touched by what he saw," Lewis said.

New Jersey Sen. Jon Corzine, the only Democratic senator, on the civil rights tour praised Frist for organizing the visit. Asked why he thought Frist put the trip together, Corzine smiled and said, "All of us do things for multiple reasons."