Source:
Leip, David. Dave Leip's Atlas of U . S. Presidential Elections.
http://uselectionatlas . org (date).
Here we only show the name of county which is large enough in cartogram, so some county name will appear and some disappear as time goes.
Hope you enjoy

.
2004:
George W. Bush Republican 1,104,294 54.77%John Kerry Democratic 893,524 44.32%2008:
John S. McCain, III Republican 1,230,111 53.39%Barack H. Obama Democratic 1,034,707 44.91%2012:
Willard Mitt Romney Republican 1,233,654 53.48%
Barack H. Obama Democratic 1,025,232 44.45%
2016:
Donald J. Trump Republican 1,252,401 48.08%Hillary Clinton Democratic 1,161,167 44.58%Gary Johnson Libertarian 106,327 4.08%2020:
Joseph R. Biden, Jr. Democratic 1,672,143 49.22%Donald J. Trump Republican 1,661,686 48.91%Maricopa, Pima, Pinal and their merry counties.