Not sure why the downvotes. A consequence of our two-party system is that both parties end up being uneasy coalitions of many different "parties."
The Republicans have long been an uneasy coalition of the religious right, paleoconservatives, fascists, economic libertarians, right leaning neocons and neoliberals, and mid-century centrist "Eisenhower conservatives." Major fault lines have been between the libertarians and the religious right and between the neocons and the paleocons and nativists.
The Democrats have long been an uneasy coalition of left leaning neocons and neoliberals, social libertarians, anti-war activists, minorities who feel threatened by Republican tolerance of racism and nativism in their "big tent," atheists and minority religions who feel threatened by the religious right, and socialists. Major fault lines have been between the socialists and the various economic centrist or libertarian factions, between socially conservative minorities and the social liberals, and between the neocons / neoliberals and the anti-war / anti-empire factions.
Each party contains at least three or four other parties within.
A shuffle seems to be happening right now where the nativist, paleocon, and fascist parts of the Republican Party have gained power at the expense of the neocons and neoliberals after the latter discredited themselves with the Iraq war disaster and the 2008 financial bailout shitshow (which can technically be blamed on both parties since Obama presided over some of it).
Another shuffle occurring is that libertarianism has really taken a hit as a result of anxiety over wealth distribution and issues with globalism and neoliberalism. Many libertarians on the right have been converted to the alt-right/fascist side, and on the left quite a few have gone further left economically and joined the AOC wing of the party.