Ron Paul, the congressman from Texas who tried to get an amendment passed to defund NAIS in May 2006 is doing an exploratory committee on a run for President. I like him because he is a strong Constitutionalist.
From his website
Congressman Ron Paul of Texas enjoys a national reputation as the premier advocate for liberty in politics today. Dr. Paul is the leading spokesman in Washington for limited constitutional government, low taxes, free markets, and a return to sound monetary policies based on commodity-backed currency. He is known among both his colleagues in Congress and his constituents for his consistent voting record in the House of Representatives: Dr. Paul never votes for legislation unless the proposed measure is expressly authorized by the Constitution. In the words of former Treasury Secretary William Simon, Dr. Paul is the "one exception to the Gang of 535" on Capitol Hill.It is good to have someone inside the beltway who actually remembers the oath of office.