In 2004 Idaho voted 30.26% Democratic and 68.38% Republican.
In 2008 it voted 36.09% Democratic and 61.52% Republican.
In 2012 it voted 32.62% Democratic and 64.53% Republican.
In 2016 it voted 27.49% Democratic and 59.26% Republican.
So no, I don't see any trend to the Democratic ticket. Not recently. In 2008 it trended that way but it has snapped back.
The Margins difference between 2012 and 2016 were almost zero. But indeed the margins between 2004 and 2008 were quite significant gains for the Democrats.
2016: 31.8% margin win for Trump
2012: 31.9% margin win for Romney
2008: 25.4% margin win for McCain
2004: 38.1% margin win for Bush
