We don't do our elections that way. Actually we hadn't been following our by-laws either, we just found them and knocked the dust off of them to make amendments and much needed updates.
We are supposed to have a nominating committee and they are supposed to find someone willing to fill the position they are nominated for, but here is how I got elected VP: I was one of 4 parents attending the other 3 said no way, so a teacher says "I nominate Carmon." Here I am almost 2 years later still in action as President though ( our prez had to resign due to family issues). I plan to resign this year if we can find someone to take it. So far we are in the same boat you are, no one wants it.
If everyone agrees, I wouldn't see what it would hurt to side step you by-laws just this once. If no one will step up volunteerly what other choice will you have?
Our bylaws are set up so that the President is President for 1 year and then the VP steps up as the President. This year we have not had anyone wanting to run for VP and our bylaws don't handle this situation. Has anyone had this happen and what did you do?