If two entities that provide something are in cahoots to keep other entities away, is that technically a monopoly? I know a monopoly is basically no competition, so what if the competitors have an agreement to at least minimize the field?

Democrat and Republican parties have worked together to keep third parties down. It's a monopoly on American politics that has left us w/dumb & dumber & a mindset of a 3rd party being a throw away or costing the loser. IT'S COMPETITION...IT'S OPTIONS.