1. Someone who subscribes to no actual political party, picking and choosing on each politician or issue's own merits.
2. Someone who subscribes to the specific Independent Party.
3. Someone who is a Democrat, but thinks it makes them seem free-thinking and individual to style themselves as being unbound by party rules.
2. Most likely puts a straight-party vote for Independent.
3. Votes straight-party Democrat, after constantly supporting Democrat politicians and attacking Republicans while bragging about independent status.