Here is a polite sample letter courtesy of HazardPerry:
An Open Letter to Fred Thompson Supporters
In a Republican party where everybody seems to have divergent opinions, it is sometimes hard to stand back and appreciate the similarities, not only between the candidates, but between a candidate and his party's platform. For many Republicans, and most true conservatives, this cycle has been a dissapointing, if not alarming one. It comes on the heels of two terms of expansionist foreign adventurism, deficit spending, wasteful government programs, gross federal mismanagement, and repeated scandal. That the very nature of conservatism has become a prime issue to Republicans is indicative of the fractures in the party and its electorate.
If you take away the names and the (R)'s and the rhetoric and look, side-by-side at the records of the Republican candidates, some trends become apparent. The majority of Republicans seeking nomination do not set any sort of conservative standard in their projects or voting record. Some could even be classified objectively as liberal! Mass amnesty for illegal immigrants? No Child Left Behind? Raising taxes 47 percent? One called Barry Goldwater an "incompetent, confused, and sometimes idiotic man." The list goes on, but the party will not, if candidates think that a hawkish foreign policy and some lipservice to small government are the only credentials necessary for success.
The Ron Paul community has always had a bit of a soft spot for Fred Thompson. He isn't taken to cackling at ideas of small government, he isn't keen on snap judgements, and he cares about the core of the Republican party. When our candidate was excluded from a Fox Debate, Fred brought up many of the same issues that Ron may have raised. While it is a competition, we always felt glad that at least somebody else understood the principles of conservatism, and the important thing was that the message was being heard. But now Fred Thompson has left us, after rough showings in states that wear their philosophy on their sleeves until it comes time to actually vote. This is disheartening, because the future of our party and of the very word 'conservative,' we feel, has now been winnowed down to one last candidate... Ron Paul.
We need a coalition of thinkers, of people who can look past the rhetoric, see beyond the posturing. We need conservatives in mind and spirit. This is our party, and it is a confused one. But we must never confuse our principles, and in that refusal, we can light the way to victory and a restoration of real values in government.
Will you join us?
Fred Thompson on the issues:
http://www.fred08.com/Principles/PrinciplesSummary.aspx?View=OnTheIssues
Ron Paul on the issues:
http://www.ronpaul2008.com/issues