Open the Tor Browser, and navigate to the voting page.
Click the S icon ("NoScript") on the toolbar, and set scotusblog.com as TRUSTED.
Reload the page.
Search for the following on the page using Ctrl+F:
4 Antonin Scalia (associate justice, 1986-2016)
Open the Storage tab of the developer tools panel using Shift+F9, and select Cookies > https://www.scotusblog.com in the left pane. Observe a list of cookies stored by the website in the right pane.
Repeatable steps
Vote for Justice Scalia.
Click the onion icon ("New Tor Circuit for this Site") on the toolbar – this will give you a new IP address.
Click the newly appeared cookie named voted_[##] in developer tools, and press the Delete key – this will remove the cookie storing the fact of the vote.
Once the voting page reloads, press Ctrl+G – this will redo the last in-page search, and take you straight to the relevant voting form.
Use Tor to vote multiple times
Preparation
Repeatable steps
Keyboard shortcuts may need adjustment on macOS.