Not a third Party. What we need is multiple parties representing a variety of views on both sides of the spectrum, like most other countries have. A third Party would just split whichever Party they branched out from and assure that they could never win an election in the vast majority or races. If Progressives broke from the Democrats, it would be hard to imagine either of them winning in any election against a unified Republican Party. If Trumplicans split from Republicans, it would insure many more wins for Democrats. If there were 5 or 6 Parties representing various factions of both, they would have to make more effort to represent the outsiders.

. . . "third party" ?

. . . for those who might not know, it has been done (many times) before :

[en.wikipedia.org]

The Dems and GOP will lock ranks to prevent that from happening, by fair means and foul. For example on the rare occasion a third party candidate gets into a state legislature, the Dem/GOP just make sure ANY bill they propose goes nowhere. So when it comes time for reelection, they just claim "Look, they got nothing accomplished!" IE the American political system is FAR too corrupt to ever let a third party in the door.

Ask those two-thirds of Americans to identify what they want a third party to do. Good luck.

Any party with enough voters to win any election anywhere will attract donors to the party’s winning candidates.

It's easier to enslave people with only a two parties system
Your owners will tell you on how and what to think anyway.

If you want a center right party, you've already got one, the Democrats.