And the statistic for this was the minuscule turnouts for the yearly elections after each of those Presidential elections. And the only time I might see an uptick is if there is a contested mayoral election (here in Philly that one is off-year from both Presidential and Congressional elections) and occasionally for gubernatorial elections (which do happen during Congressional cycle years here in PA). It's sad. At least for our last gubernatorial one in 2014, we were able to get a Democrat in but he is up in 2018 and we have to make sure we keep him in due to the 2020 census and redistricting.
The one thing I have noticed is that there is so much GOTV effort, media attention on local music stations and TV (and often drama) during Presidentials that is missing during other years, that it's as if people are "exhausted" and are ready to hibernate for the next 3 years. And so we suffer because those in the rural areas then dominate the governor's office and state legislature because the cities sit it out.... resulting in gerrymandering and being completely shut out from drawing the district lines. 
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