The utility does not work for me, but I assume my surname "Dunn" is pretty heavily Dem, since I suspect a substantial percentage of Dunns are black, given that the name is most common in the South, and thus there were a lot of Dunn slave masters out there.
Not particularly. It is 54% D, 46% R.
It is the 167th most common name, 152nd Republican, 187th Democratic.
The South is erratic. 70D-30R LA, 39D-61R SC, strongly R is AL and TN, weakly D in GA, weakly R in FL.
There is Democratic concentration in the Midwest, centered on Minnesota. Utah is 79% R, perhaps some Mormon Dunn's.