They should look for someone that believes in the US Constitution as it was written, not re-interpreted.
So someone who believes the Federal government should only be involved in national defense, and not in education, environmental protection, labor protection, farm subsidies, health care, retirement funding, communications (including Internet), roads and highways, regulation of banks and the market, etc.
Feature creep or cherry-picking the principles you feel are worth defending. Pick your poison.
Someone appalled at how the CIA has been allowed to run amok and trample all over the freedoms guaranteed by that document.
Actually the CIA for the most part isn't bound by the Constitution. The CIA's mission is to protect American interests abroad, where the Constitution doesn't apply. The corresponding TLA organization who operates within the U.S. is the FBI. One can argue that from a moral perspective the CIA should be operating abroad by the same principles they are purportedly defending at home. But there's no such legal requirement. And mathematically that seems to be an ineffective strategy (tit for tat turns out to be one of the best strategies in the iterative prisoner's dilemma, whereas always being nice consistently results in being taken advantage of).