People who truly benefit are extremists on both sides: every time an idiot on one side says or does something, an idiot opposing him sends a fundraising email to fight the “other guy”. They feed on each other.
This is what was happening in Weimar republic: some people voted for Commies to fight Nazis, and others – for Nazis to fight commies. One can even argue that, as terrible as Nazi win was, it would have been worse if commies would have won and formed a united Stalinist union from Japan to France.