“The obvious assumption is that his potential candidacy freezes the race, that he dominates the field like a colossus and sort of smothers any other Republican presidential efforts. There’s also a possibility, given financial challenges, potential legal challenges, and the undignified way that he has conducted himself since the election, where he is a substantially diminished figure in the not too distant future,” he said, citing Sarah Palin as an example of a once-Republican star who became a marginal figure far more quickly than many expected.