Republican vs. Democrat strength since 1856 to the present graphed.
How do you measure party strength? The Presidential elections?
One need only look at fights over voter identification laws, redistricting, food stamp benefits, Obamacare expansion, and a multitude of other battles from the last few years alone to understand the importance of non-federal elections.
This article’s conclusions uses 5 election metrics: Presidential, Senate, House, Governors, and State Legislatures. It adjusts for votes as well as number of elected officials in certain categories.
Using this methods, it graphs Republican vs. Democrat strength since 1856 to the present. Interesting and informative view of U.S. political history.