Followed this simple process to review sites:

1. Check for Optimizely, VWO, mboxes or any signs of other client-side a/b testing tools on the site.
2. If yes, then look at active experiment code. While I know Hillary’s team is testing and there are a few experiments still not archived, there’s nothing worth mentioning. I posthumously found more experiments being run by Jeb Bush (no longer relevant) and Ben Carson: https://medium.com/soapbox-dc/what-are-jeb-bush-others-a-b-testing-676b231f094f

In any case, looking at all presidential campaign sites, there is no sign of any structured conversion optimization strategies. This is based on the types of tests, naming conventions (e.g. “Splash page — Third tests”), and lack of insight flow between tests.