That's true. I often take things too personal.
I know the person who's running personally. We both went to the elementary school here and the high school in another town. The person who endorsed him is the wife of our 8th grade teacher.
No, it is not. The wife holds weight in the community and is already on the committee. The person running is more known here than me too.
You missed one step though: you used Facebook. You really cannot trust Facebook as a good measure of whether you are reaching people because the system itself filters out messages that it would 'think' might be important.
For example: you have 5 people from that school on your friends list and listed no previous interest in the field of the position. He has 10 people from that school on his friends list (and probably never talks them either), but has, once, listed interest in that field. His message will get shared as an 'important' story, whereas yours will not. People's preference filter in only the 'important' stories, and therefore she simply never saw your original message.
This gets way worse the more friends you have and the more diverse they are, since facebook then starts to select more aggressively. Considering the second person is female, her list is twice as large as the same person as male by default (yes really, this isn't a stereotype, that just happens on every medium, ever), so she would be a prime target for this scenario.
So you would assume many things when Facebook might have simply crapped your party from the first move by being ****ing Facebook. It does that a lot, so it's not like this would be the first time.
Use a mail listing and / or newsletter instead. You know it gets to people when you send them (e-)mail, but unless you're a company and you're providing money to facebook, you would never be certain of it.
Second option scenario: they are opportunistic cunts, and now it's your job to ruin their ****ing day by calling or mailing EVERYONE. Guy wants to compete? Crush the fool.
(he would do it to you, if this scenario applies. Besides: if it's a game, you play to win)
Is this likely? A cynic would say 'yes', but I doubt it's what happened. Either way: just crush the guy. It's a game, crush him.
Good luck with the run.