As a student at UWM you have access to the full suite of ArcGIS including the ArcGIS Online web application.
See the information on UWM's software page about getting access.
ArcGIS Desktop can also be found on most public access (Windows) computers on campus!
Use Mac, Linux, or an older PC that is slow to run heavy software? Consider the Free and Open Source QGIS as an alternative to ArcGIS.
The Wisconsin State Legislature's Open Data Portal:
Homepage: https://data-ltsb.opendata.arcgis.com/
About: The Legislative Technology Service Bureau (LTSB) Open Data Portal exists to provide easily accessible open data of a legislative nature for the state of Wisconsin.
Data Available: Available on LTSB are freely downloadable spreadsheets (CSV), KMLs, GeoJSON, and shapefiles of Wisconsin.
Topics Include: Legislative Districts, WISE-Decade, and Election Data