I basically agree with John Hawkins’s summary of the situation.
Thompson is the most authentically conservative candidate with the best potential to win. Romney could fail to carry the South, and Giuliani is a liberal pretending to be conservative.
Thompson is definitely much more representative of the vision of the Republican Party that people had in 1980-1994 — than he is of the “Big Government Republicanism” vision of the GOP that George Bush has come to represent. That means that Fred Thompson could be someone conservatives really want to have in the White House, as opposed to a candidate who could only be said to be the “lesser of two evils” when compared to Hillary Clinton or Barack Obama.