The library subscribes to this statistics-only search engine. It's great for finding data on a range of topics - including political spending and public opinion - but also good for figuring out who collects data on a topic you're interested in.
Note that when you use data from Statista, you should cite the source of the data, not Statista itself. Statista is just the search tool.
Follow current legislative action in the House and Senate. You can find a page for each House or Senate member (ex: Sherrod Brown) to see their voting records, committee assignments and remarks in the Congressional Record.