'A storm of the century': New data reveals why 2018 was such a massive landslide for Democrats — and bodes even better for 2020

Democrats succeeded in fueling the hoped-for "blue wave" in 2018, flipping control of the House of Representatives and securing a decisive majority of 38 seats.  And new data analyzed by Michael McDonald, who studies elections as a professor at the University of Florida, helps reveal why Democrats were able to win so big.

The Census data shows that in 2018, the share of the voting population that was non-Hispanic white dropped compared to 2016:

Since white voters disproportionately vote Republican, and people of color are more likely to vote Democratic, this shift strengthens the Democrats' chances.

But as McDonald noted, and as the chart above showed, this is not a typical pattern for a midterm election.

"Usually, the midterm electorate becomes a shade whiter than the last presidential. Not true in 2018 compared to 2016," he explained. "The 2018 election saw the highest midterm turnout rate since 1914, so I expected the midterm electorate to more demographically like a presidential, but I did not expect to see the non-Hispanic White share of the electorate actually drop from 2016."

This shift could be partially explained by the fact that in 2016, black voter turnout was down compared to 2012. This is consistent with the graph above showing that, even though the overall non-Hispanic white portion of the electorate shrank from 2012 to 2016, the decline was much smaller than it had been in recent cycles.

Another key demographic that represented a large share of the electorate in 2018, giving Democrats a boost, is the younger cohort:

"What does this all mean for 2020?" said McDonald. "We are likely in for a storm of the century, with turnout levels not seen for a presidential election in the past 100 years. It is likely persons of color and younger people will participate in 2020 at unprecedented levels"

McDonald didn't speculate about the causes of the shift in the trends, but the most obvious explanation is President Donald Trump. Despite a relatively strong economy, his approval rate is pretty abysmal. And his presidency has been a gripping tale of controversies, scandals, and outright presidential abuses and neglect that have likely roped many more voter in and drawn more attention than a comparatively uneventful administration would have. The groups most opposed to and threatened by the GOP and Trump agenda were thus more likely to turn out in 2018. If Democrats are able to play their cards right, and Trump doesn't manage to stir up comparative enthusiasm on the right, the GOP might face another blowout in 2020.