I am not a political scientist or a political historian. My understanding is that the United States has operated under a two party system almost exclusively. Third parties and persons who seek political office outside the Republican and Democratic parties have had scant success during the past 150 years. It is fair to say that the sounder advice for anyone seeking a political path would be to try to do so in either the Republican or Democratic Party.
Are the sands shifting? There is reason to think, from the past three years in particular, that maybe they are. No one knows, and only time will tell.
We know that sands will shift only if some people take steps to try to shift them. All will play out in due course whether the sands will shift.
Suggested link: http://www.independentvoting.org/
The events of the past three years seem to me to be a sufficient basis for trying to shift some sand in the 6th Congressional district in Alabama.