Here we can contrast elections

[MarkD]

Have you ever compared the presidential election of 2000 in New Hampshire to the election of 2016 in the same state? It's remarkable how similar most of the counties voted, with two exceptions, and those two exceptions show the reason the state voted Republican in 2000 but Democratic in 2016.

Statewide, Bush won 48.1% to 46.8% in 2000. But in 2016, Clinton won 46.8% to 46.5%.
Here is how each of the counties voted in the two elections.
       County                      2000                              2016
Belknap County -       55.2% R to 40.0% D       55.1% R to 38.6% D
Carroll  County -     52.8% R to 41.3% D     49.4% R to 43.9% D
Cheshire County -      41.3% R to 52.1% D       40.3% R to 52.7% D
Coos County -            50.2% R to 45.0% D       50.9% R to 42.0% D
Grafton County -      46.7% R to 47.3% D    37.1% R to 55.7% D
Hillsborough County - 48.7% R to 46.8% D       46.7% R to 46.5% D
Merrimack County -    47.2% R to 48.1% D       45.0% R to 48.1% D
Rockingham County -  49.1% R to 45.9% D       49.9% R to 44.1% D
Strafford County -       42.7% R to 51.4% D       42.1% R to 50.6% D
Sullivan County -        49.8% to 44.1% D          47.6% R to 45.0% D

Eight of the counties voted almost exactly the same way in 2016 as they had in 2000, but Carroll and Grafton Counties both shifted much more Democratic - Carroll County shifted 6.0 percentage points more Democratic and Grafton County shifted 18.0 percentage points more Democratic. Without those two counties shifting as great as they did, Trump would have won in 2016 and all of the counties would have voted almost exactly the same way in those two elections.