more attention to both the Libertarians and the Greens,
probably a party which was socially liberal and fiscally conservative,
maybe a party which tries to matter-of-factly critique the corporate state and provide doable alternates and experiments ? ?
a party which is all about high-tech and spending big money on the space program ? ? ?
a party which rails against the Walmartization of America and tries to describe real conditions faced by real people. "And people who aspire to the Middle Class" becomes one of their slogans. Maybe similar to several of the above, but their own flavor ? ?
a party all about home schooling and unschooling,
a party which becomes the de facto party of disability rights. And perhaps the Aspergers-Autism Spectrum catches the public's imagination as something which is both a disability and a difference. Yes, that's what we've been trying to explain to you.
a party all about entrepreneurship which emphasizes that it's usually about Mickey Mouse ticky-tack state and local regulations. And which really emphasizes that 80% of new businesses fail (typically because fixed expenses eat you alive) , and think it's irresponsible not to emphasize this fact front and center.
and plus a whole slew of kooksville parties!!
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And the resulting coalition governments? Sometimes more effective, sometimes less.
The PoD was in 1940s, I doubt there would even be a Green Party or a Libertarian Party to begin with, and when there is, there votes would probably be taken out by pre-existing third parties. I think you are probably estimating a few too many parties, I think several of them would merge with one another. Once things had died down after an initial realignment, I reckon you would see
-A social democratic party, composed chiefly of progressive democrats, who aim to create a welfare state along european lines, and are likely a pro-civil rights party
-A more centrist, more pro capitalist, and somewhat socially liberal party(in comparison to the right at least)
-A right wing party mainly incorporating dixiecrats, that is mainly defined by its pro segregationism, which in time might develop into something like the modern republican right
You might also get a few more minor parties if the system doesnt require high thresholds, probably some kind of communist/broad tent leftist party coalition capable of winning a seat or two. A few single issue parties are also possible, probably an agrarian Party, and perhaps a racial equality party too whose support is concentrated among ethnic minorities, particularly African Americans. In a few decades, perhaps some of the modern third parties might make minor breakthroughs, but I'd imagine they would be mostly squeezed out in favour of the more radical on there side of spectrum parties that already exist with considerable representation.