Higher attendance at individual demonstrations correlated with more conservative voting by congressional members and a greater share of Republican votes in the 2010 election, when the GOP won back the House, he said. But, Veuger cautioned, it wasn’t automatic. The tea party activists also went home and volunteered in local organizations that helped change the electoral results.
This is the crux right here. Dems have historically had trouble with longterm follow-through. Trump could be a gift, however - his continued shenanigans will keep the angst levels high.