He is technically the Supreme Commander of the Korean People's Army and Chairman of the National Defense Commission, a position with great power and does not require elections, and, of course, he's General Secretary of the Workers Party of Korea, so he runs the whole show.
Yes, Kim Il-sung is technically the President even though he's dead, but as you said, he's the Eternal President.
There is a de facto head of state, and his name is Kim Yong-nam (no relation to Kim Jong-il, and the name Kim is very common among Koreans around the world), the Chairman of the Presidium of the Supreme People's Assembly. In theory, he, Kim Yong-il (as mentioned before, the name Kim is very common among Koreans), the Premier of DPRK and Kim Jong-il each hold one-third of all executive power, but in practice Kim Jong-il holds all power.
Imagine if we were in Soviet, we are in its election, the candidates who were in the election would be checked by the Communist Party, and we usually have ONE candidate only, and we wouldn't got the choice to against him/her, thus, votes mean fors.
most of the Communist Party in strong nations don't allow democracy, such as China, Soviet, and also N.Korea.
I hate this FAKE democracy, we need real democracy.