Well, maybe trying to bring concept of “base” from chemistry could give us insights. Bronsted base is something capable of absorbing a proton [not usable for us, at least not directly], while Lewis base is the source/carrier of unshared electron pair available for binding. Similarly, political “base” could be seen as a source/carrier of “ideas” [usually half-baked in any mass implementation]. More, the base ideas better be wrong - but simple and catchy, i.e. infectious. The test of the “base idea” is its capacity to form slogans, like “workers of the world, unite!” The right ideas normally do not make good slogans, and take too much effort for comprehension and transmission, i.e. have low affinity for the potential recipient [aka voter to be attracted]. Thus one could say that their Lewis basicity is low.
Typically I distrust analogies like the one you presented, but as analogies go, that’s pretty good.
I would counter that the slogans adopted by a “base” are:
A)A short hand for broad and more complex ideas that aren’t always perfectly understood by even the base, i.e. “workers of the world unite!” or “dyslexics of the world untie!”
B)there is some other broad idea or demographic that unites a base other than slogans.