It sounds like one-hundred to one odds if each weapon had a citizen to handle it. I bet that's better than the odds of slipping on ice. It may not be possible to know how many patrolmen or troopers, if asked to take up arms against their brothers and neighbors, would ditch the powers that be and join the citizenship patrols, but it is not as if there is not a precedence.
It wont be 100 million gunowners against the military. It will be 30 well armed troops against a family or a couple men. It will be piecemeal as they seek to divide and conquer. Oh and that family will have been labeled as weapons dealers or terrorists. In exercises already completed they did house to house searches for ‘weapons dealers’