Because you asked …

In the comment section, Taryn Thompson asks: “What was the turnout before the closed primary? I don’t ever remember it being that great.”

Answer: The Idaho GOP won its suit in 2011 to close its primary. So the first closed primary vote was in 2012. Here’s the statewide primary turnouts, dating back to 2000:

Closed Primaries:

2016: 23%
2014: 26.1%
2012: 24.45%

Open Primaries:

2010: 27.1%
2008: 25.3%
2006: 25.9%
2004: 26.79%
2002: 32.3%
2000: 33.4%