They weren't "lower middle class." That's certain. They're the same sort that always lead revolutions: Disaffected middle and upper middle class persons who have more than an average level of education and intellect but cannot break into the upper class due to background, lack of connections, or some combination of other reasons that hold them back.
The lower middle class, or working class, aren't the ones that lead revolutions. They may go along with a revolution if they see some advantage in doing so, but they're typically the least likely to upset the apple cart. It is the unskilled worker, and lower class that the leaders of a revolution get to do their dirty work. These people too are disaffected by their status in society. They erroneously think that society owes them something much like the leadership of the revolution does. The only difference is they're too stupid and lazy to do much on their own without being prodded by those leading things.
