This is based on the fabulous work done by They Vote For You.
They rate each politician's strength of voting on a policy - that goes beyond just did they vote 'yes' in the final vote so you get some delineated sense of the politician's strength of conviction. However that differentiation rarely flows through to the final vote for major party members - they almost never go against the whip and rebel.
We've taken their ratings and compared only those times that the two politicians voted on the same legislation. And then we hit it with some maths.
It should be noted that while we make no overall claim to great accuracy, comparing Rep and Senate votes is even less useful than that. It does give you an indication of what's going on though.
If you'd like to dig into a politician's voting in more detail see our other gadgets: How Pols Vote
Data is dynamically drawn primarily from They Vote For You via their API and used, with thanks, under their Open Data Commons Open Database License.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
This is offered entirely 'as is' and should not be relied upon for any decisions of any sort.