https://www.270towin.com/maps/OxnXQStarting from 1856, when the Republican Party has their first chance to compete.
On the map, it's noticeable is how recent modern US political patterns have emerged. The only modern elements you can find influence from are Washington, Minnesota, Massachusetts, and Rhode Island. The New York, New Jersey, Delaware, and Maryland situation is much more post-civil war politics up to 1896 in combination with modern day politics. The Solid South is prominent on this map. And so is the old Republican allegiance of the North and Midwest.
And Washington is an outlier. It became a state much later than Oregon.
Third parties not included in either total. Not even the Liberal Republicans in 1872, who replaced the democrats that year.
