How does political extremism play out in American politics? Two new political science studies perhaps provide some insight into how public policy might evolve after the presidential election on November 8. One study shows that extremist arguments can be effective in shifting public policy debates. Another reports that since 1948 American voters have not penalized more ideologically extreme presidential candidates. The upshot is that if the predictive models are working, then Hillary Clinton should be losing due to weariness with the incumbent party and a relatively lousy economy. On the other hand, Donald Trump's extremist ideology—if you can call the mish-mash of his often contradictory diatribes an ideology—may undermine the claim that ideology plays essentially no role in determining the winners of American presidential elections. We'll see soon if these theories pan out.