Eighth in an occasional series examining candidates seeking the Republican and Democrat nominations for president and happenings along the campaign trail.

With so many appearances of late, the bigger surprise would have been if Fred Thompson had opted out of the presidential race.

Few politicians trek to the Iowa State Fair in mid-summer because they like meat on a stick that much or shake hundreds of sweaty palms in front of the butter cow because they are so passionate about the dairy industry.

No, even casual political observers probably guessed Thompson was going to run. He did not make it official, though, until Thursday during a visit to the "Tonight Show with Jay Leno."

Critics will try to dismiss Thompson as a lightweight best known for reciting someone else's lines. He has an accomplished career as an actor and has worked some of the biggest names in Hollywood: Paul Newman, Sean Connery, Clint Eastwood, Tom Cruise, Kevin Costner, Nicole Kidman, Bruce Willis, Danny Glover, Robert DeNiro and Gene Hackman

But Thompson is far from a hollow suit. He earned a law degree from Vanderbilt University in 1967 and within two years was an assistant U.S. attorney in Tennessee. He first went to Washington, D.C., in 1973, serving as minority counsel to the Senate Watergate Committee, a tough introduction to national politics.

Thompson's line of questioning revealed the tape recording system in use under President Richard Nixon. He has, however, admitted funneling information to the Nixon administration. Expect opponents to swing that tidbit with a vengeance if Thompson's campaign grows into a more serious threat.

In another investigation, as chairman of the Senate Governmental Affairs Committee, Thompson - then a senator representing Tennessee - established a link between the Chinese government and donors pumping money into the Democrat Party when President Bill Clinton was in office.

Conventional wisdom suggests primaries and Iowa's caucuses attract each party's base. For Republicans, that means conservatives, and Fred Heads - Thompson's most faithful followers - believe this gives their man a leg up on the competition.

Thompson's Web site lists political influences: Barry Goldwater and Ronald Reagan. Those names will fall like music on conservatives longing for a candidate promoting their ideals. American Conservative Union, a lobbying organization, in 2002 gave Thompson's lifetime voting record an 86 percent approval rating, for instance.

An overarching principle Thompson frequently offers is limiting the reach of federal government. One recurring theme - going after wasteful spending - may play particularly well in Iowa. Our own Sen. Chuck Grassley has pursued similar efforts, and he has been a voter favorite since 1959.

Thompson's health may become an issue, though it's doubtful opponents will gain much leverage. Thompson, 65, reportedly has a relatively mild form of non-Hodgkin's lymphoma. He says he is in remission and that medications will manage the disease very easily. Two other prominent Republican candidates - Rudy Giuliani and John McCain - are also cancer survivors.

Early chatter focuses on the timing of Thompson's announcement to run. It seems like a non-issue Thompson addressed on Leno's show.

"If you can't get your message out in a few months, you're probably not ever going to get it out," he said.