Senate.gov provides a list of senate votes under the Legislation and Records heading. On the Legislation and Records page click Votes for a list of recent votes. Click the year links under the Roll Call Tables heading for all votes during a specific year, back to 1989.
Senate.gov only lists roll call votes. Other types of votes are available on Congress.gov; however, voice votes, in which members say "aye" or "no," and standing votes do not list how a particular member voted. Like Senate.gov, Congress.gov lists senate votes back to 1989.
Congress.gov provides access to the Congressional Record, the full official record of the Senate and House, including both the floor and committees. The Daily Digest section of Congressional Record, posted on the main Congress.gov Congressional Record page, summarizes the day and lists page numbers for each vote. Click Entire Issue for the full Congressional Record of a particular day. Use the Date box to find previous issues back to 1995.
Other third-party websites, such as OpenCongress.org also list voting records for both the Senate and the House. Use the search bar to search to find specific votes, individuals or even broad issues. Click the Votes link for a list of all recent votes, and click Votes on Major Bills to narrow the list. OpenCongress.org only lists roll-call votes.