Perhaps what is needed is a “new” party but not a third party (no one wants to be a third party in a system dominated by two parties). If this possibility is made to appear serious, the R party will definitely take notice—they know a new party would eviscerate their fund raising and support. Something new tends to excite and attract people and people are looking for something fresh. The key to all this is the ability to gain current Dem party members—that is what must be addressed in any new party strategy. If that is done effectively (following development of a fund raising strategy), then enough voters and support can be gathered from the other two parties to make a dent in elections. At first it would need to be a typical European multi-party situation where the other parties would have to form alliances with the new party to gain sufficient support to win elections. Ultimately, a new party could take the lead but that is for later.
"Independents" who run on repeal of Obamacare, tax reform, energy and jobs. That's it. Pledge that for the next two election cycles absolutely no discussion of "social issues". In order to save America, we will "agree to disagree" on social issues.