"sympathizer" in the noun sense
1. sympathizer, sympathiser, comforter
a person who commiserates with someone who has had misfortune
2. sympathizer, sympathiser, well-wisher
someone who shares your feelings or opinions and hopes that you will be successful
Source: WordNet® (An amazing lexical database of English)
Princeton University "About WordNet®."
WordNet®. Princeton University. 2010.
View WordNet® License