A nice moderate party? I might just join that
Of course, currently we have three "Third parties" in the United States and have had them for a while
Constitution Party (the third largest political party in the US by the way)
Green Party
Libertarian Party
and those are just the big "third parties" if you want to consider the smaller "third parties" we have a bunch of them
American First Party
America's Independent Party
American Patriot Party
The American Party
Independent American Party
Prohibition Party
Working Families Party
The New Party
Labor Party
Socialist Party USA
Communist Party USA
Socialist Labor Party
Party for Socialism and Liberation
Progressive Labor Party
Socialist Equality Party
Socialist Workers Party
World Socialist Party of the United States
Workers Party, USA
Workers World Party
Centrist Party
Independence Party of America
Modern Whig Party
Reform Party of the United States of America
It is not that we don't have a "third party" it is more like we have too many "third parties" that can't get organized.