noun, 1. Overzealous supporter. 2. Surprise-attack accoster. 3. Anyone wearing more buttons than articles of clothing. 4. A bad person in support of a good person.
"Hey, sorry I'm late for work. I was nabbed by a gaggle of obamatrons."
"The show was great, except that there was an obamatron in the front that yelled after every single word the singer said.