Political Thought: Primary voters

The New Hampshire Primaries are today.  The number I'm curious about isn't who wins, but the total number of primary voters.

In 2016, there were 253,062 votes for the Democratic Primary.  In 2008, there were 287,557 vote for the Democratic Primary.  In 2004, it was just under 218,000 votes for the Democratic Primary.  

This year, there are multiple candidates on the Democratic Primary, and it's an election where they are trying to vote out a disliked incumbent President.  

New Hampshire voted Democrat in the 2016 election, but it was close- 46.7% to 46.25%.  For the Democrats to win in 2020, they need to keep all of the states they won and flip some of the others.

In theory, passions are running high- not only for their candidate among the Democrats, but to vote out President Trump.

The turnout in the Iowa Caucus was low- but Iowa had so many problems that I'm not sure it's a good example.  But if New Hampshire has a low turnout under these circumstances- a close Primary election in a year they should be passionate about throwing out the President- then I would be very worried that too many voters have just tuned out completely.