You may not know this, but Sudan is ruled by its Muslim, Arab north and is often quite happy to enslave or murder the black Christians in its south. Hardly a model of an anti-Islamist republic.
He is a Sufi (mystic, esoteric) and more than a bit eccentric. I saw his brand of Islam described as "New Testament" elsewhere. He has tried to argue (contrary to most Islamic scholarship) that the earlier peaceful Meccan sections actually abrogate the later warlike Medinan sections of the Quran. I don't think he's any sort of Islamist at all.
"He says he has serious issues with the hardline, traditional readings of the text, and he's writing a book about his reading of the Koran -- with working titles like Jesus Among Us With the Quran, or The New Understanding of the Quran."
http://www.dallasobserver.com/news/why-mohamed-elhassan-the-...
He ran for the National Reform Party. Here's his website: https://web.archive.org/web/20110903180626/http://www.alisla...
Note repeated use of the word "sufi".
EDIT: He tried to repeal laws against converting from Islam and ratifying human rights. That's not the stance of Islamists. http://www.vox.com/2015/9/16/9339063/ahmed-mohamed-elhassan