I don’t know what political party he favored, but his raving lunatic mind was very upset with amoral people and immorality in todays society which he attempted to explain in his admiration of Hitler, and again in this snippet of his manifesto where he lauds Obama as being more effective in tearing down that immorality then Tim McVeigh was. (that means he wanted the country to crash and burn and Obama was the best way to do that)
So if that means to you that he was a demorat, or a lefty, then carry on....It does not matter in the long term.
I would prefer to call him a nutcase anarchist. His politics, if you want to call it that, was at best undefinable at worst, off the scale on both left and right.. He was off the chart where the nuts live on both political sides.
Although a bit grainy, it appears to be the same flag cherished by these DemonKKKrats:
So, it sure seems to me that this evil murderer has an affinity for the same flag cherished as part of their 'RAT heritage. Ergo, applying basic Aristotelian logic, one must conclude that John Russell Houser was a indeed a liberal DemonKKKrat.