A political party is an aspect of real world power structure in which Greens, Reds and Blues (and in some systems even Pinks) get their own faction formally represented as a political party that runs for elections. This is one response to worst cases where one may run into the possibility that one must either democratize or destroy one's own project.
The existence of formal parties is often thought to lead directly to un-needed factionalism. This seems unlikely to be true, as, there are literally no democratic political structures in the real world without such parties. They seem to be absolutely necessary to agree on factionally defined terms.