Labor Party: Despite being nearly outlawed during the Red Scares & the McCarthy era, this party (which first emerged from obscurity in response to WWI veterans' anger over their loss of jobs, then gained major traction during the Great Depression & the collapse of the Big Two parties) is still going strong. The promise of federal funding to tech industries is helping to maintain support among those voters who aren't among the more traditional workforce.
Liberal Party: The main conservative party, both socially & economically, with a large libertarian faction.
National Party: A christian democracy/social justice party. Due to America's increasingly secular nature, they're not big outside of the Bible Belt, with the exception of Utah. As a result of this, they tend to ally with the Conservatives, often running fusion ballots, sometimes even to the point of being given the VP slot on presidential tickets.
Green Party: Labor's main ally/friendly rival, founded by members of the progressive wings of the former Democratic & Republican parties coming together after their old parties collapsed during the Great Depression. Whereas Labor is primarily focused solely on policies related to ensuring a more prosperous & safer employment environment for all Americans, the Greens have a broad platform of left-wing policies, having long been champions of environmental issues, as well as civil, women's, & LGBT rights.
United America Party: The successor to The Alliance For American Unity, the coalition of various state parties & Democratic & Republican factions which FDR & his allies brought together to help the country through the Depression, the collapse of the two party system, & WWII. By the end of the war, the party had coalesced into its current form, a mostly centrist big tent which has a wide support base, which usually allows it to serve as a kingmaker in Congress & during contingent presidential elections.
How about One Nation (I imagine Bob Katter is a senator for South Carolina or somewhere similar.
