It's important to remember WP:NOPV when editing articles. Your edit constituted vandalism as it was portraying the party in a negative light. I'm fairly sure any other editor would have used that template. That's not me being POV, that's me attempting to be neutral. Besides, this sentence has now been removed altogether so there's little reason worrying about it now! What I would probably suggest to you if you haven't already is that you create an account for Wikipedia (of course you don't have to - just a suggestion - but a lot of editors are often suspicious of anonymous editors).