What does the original constitution say about voting?

Only that citizens have the right to vote for a US Representative if they are able to vote in the largest house of their state's legislature. People did not have the right to vote, granted by the Constitution, for anything else including Senators and the President/Vice President. Some states did have popular voting for Senators and Presidential Electors at the time, but it was not required. It is still not required for states to allow popular voting for Presidential Electors, however all states practice this.