I'm a big supporter of the FairTax, too; I think we should get rid of the income tax altogether. But I also want to make abortion illegal, and adopt a Federal Marriage Amendment, and plenty of other things, and I think Butler would increase our odds of achieving those things, since (i) I think he has a better chance of winning, and (ii) as a black conservative, he would be a better spokesman for getting blacks around the nation to support those goals.
1) Zandstra is 100% on board with the FairTax.
2) Abortion is no longer up to the legislature. It is left to the supreme court.
3) Any ammendment to the constitution is dang near impossible at this point in time.
Keep in mind the only thing the Senate can really effect is fiscal policies.