Once you get driven down into the twenties as a percentage of voter identification, in a two-party system you are pretty much out in the wilderness for at least a decade.
Maybe the GOP makes a push for a parliamentary system in Congress, which--in this particular fantasy--would envision their rebranding as the American Conservative Party and actively encouraging the break-off of, say the Progressive Party to the left of the Democrats and the demolition of the barriers that prevent the Libertarians, Greens, and Constitution Parties from ballot access around the country.
Democrats, after all [thanks, Will Rogers] have a way of destroying their own internal party unity on an issue-by-issue basis, and with most polls suggesting that at least 10-15% of the Dems are further into the Progressive category than the current administration, as well as that at least 10% of people have decided Libertarian leanings, we'd get an interesting free-for-all.
The only drawback to this strategy (aside from that rather mundane objection that there's really no mechanism in existence to put it into play) is that the GOP would have to give up [publicly] on the idea that most Americans are social conservatives at heart.
Hell. Freezing. Over.
But just for a moment I had a glimmer of hope that a Libertarian could get elected somewhere to something.
Back to watching for Missouri Highway Patrol cars in my rearview mirror.