Is it typical for colleges to cancel a course well into the semester? What options does an instructor have in this case? I'm teaching as an adjunct at a community college in the US. One of the courses I'm teaching has very low enrollment. Now, several weeks into the semester, the college is considering cancelling the course. I am not happy about this as it would significantly impact my income. The course is unusual (for reasons I won't go into in an attempt to preserve anonymity), and had I anticipated that low enrollment might lead to cancellation I might have chosen one of a couple other employment options this semester instead.

I can look into the legal aspects elsewhere, but I wonder whether this is a common scenario? Do instructors in this situation just accept the loss of income? I never encountered this before my previous teaching experience.
I have seen this happen at community colleges, although perhaps not past the two-week point.

I hope you have been actively trying to promote interest in your course!

At this point, your best bet, to try to keep the course alive, may be to gently try to get some of your students to lobby for keeping the course.  Be careful how you do this.  You don't want to give them the feeling they are on a sinking ship.  You can just mention that the enrollment is low, and it would be helpful for all concerned if the students were to let the department know that they feel the course is important for them, in their program of studies, and important for the department.