Whoever wins the Democratic nomination, 2016 will go down in history as the year when liberals took over the Democratic Party.
Don't believe me? Just look at the image above. It shows a massive increase since 2008 in the percentage of the Democratic electorate in Iowa, New Hampshire and Nevada that self-identifies as liberal.
In Iowa, liberals went from 54% to 68% of caucus-goers.
In New Hampshire, liberals went from 56% to 68% of primary voters.
Nevada saw the biggest jump of all, with liberals rising from 45% to 69%.
In all three states, liberals went from roughly half of the Democratic presidential nominating electorate to a little over two-thirds.
The liberal surge among Democrats has been so dramatic that there has actually been no decline in liberal turnout in the early Democratic nominating contests since 2008, despite overall turnout declines of 22% in these contests.
Taking the total turnout in each Democratic contest and multiplying it by the percentage of self-identified liberals in the entrance / exit polls of those contests, here is how 2008 and 2016 compare on liberal turnout so far:
Iowa: 129,500 in 2008, vs 116,400 in 2016 (down 10%)
New Hampshire: 161,024 in 2008, vs 170,662 in 2016 (up 6%)
Nevada: 52,650 in 2008, vs 55,200 in 2016 (up 5%)
Total in all three states: 343,204 in 2008, vs 342,216 in 2016 (even, well inside the margin of error for this study)
In 2016, liberals are showing up at Democratic presidential nomination contests in just as much force as they were in 2008.
By way of contrast, the combined turnout of moderates and conservatives in Democratic contests was down 50.4% in Iowa, 36.5% in New Hampshire, and 61.5% in Nevada. Overall, it has declined by 46.9%, representing all of the overall Democratic decline.
(You can find all of the math I used to produce these numbers here.)
Whatever the causes of this shift, it is decisive. The old days of a moderate-dominated Democratic Party, or even of a Democratic Party split roughly evenly between liberal and moderate-conservative wings, are over and they are not coming back. Consider the following:
The percentage of both the national population and the Democratic Party that self-identifies as liberal has been consistently on the rise for more than a decade. Both Pew and Gallup have documented this change in detail.
This trend is certain to continue, as younger generations are overwhelmingly more likely to self-identify as liberal than older generations.
All of this will create a feedback loop, as candidates seeking Democratic nominations will have more incentive to appeal to liberal voters and less to moderate voters. Simultaneously, this will give liberal voters more of an incentive to participate in Democratic primaries, and moderates less.
Leadership of the party at all levels--presidential, congressional, state, county and municipal--remains dominated by moderate New Democratis. This will most likely not change overnight, nor will change at an even rate. Generally speaking, leadership of powerful institutions tends to lag behind changes taking place at the grassroots level.
However, whether it takes one decade or two--or whether it even happens in 2016--change to the leadership and direction of the Democratic Party is coming. The forces behind this change are too powerful for anyone to successfully oppose over the long-term.
We are already seeing this change play out in the current campaign between Hillary Clinton and Bernie Sanders, where the policy debates are occurring in a space far to the left of any recent Democratic nomination campaign. Social security expansion, debt free college, meaningful criminal justice reform--this is just a taste of things to come. Liberals have finally taken over the Democratic Party, and there is no going back now.