A "Vote" is an expression of your opinion about the available choices.
Sadly, many Americans have become brainwashed into believing that the only possible kind of vote is "please name exactly one candidate, then shut up." (That kind of voting is called the "plurality system.") This is an incredibly bad kind of vote because you only get to give information about one of the candidates, i.e. the minimum amount of information you possibly could provide. It is as if this system was intentionally designed to minimize your input rather than to maximize it.
But other, more expressive kinds of votes are possible! One kind, advocated by J.C. de Borda in 1781 and (used in a different manner) by the Marquis de Condorcet in 1785, is a rank ordering of the candidates. For example, if the candidates were Alice, Bob, and Cathy, you could order them Alice>Bob>Cathy, meaning Alice (in your opinion) is the best. That is much better because you get to give information about your feelings about more than just one candidate! But this kind of voting still is not as good as it could be:
Range voting overcomes all those problems -- you can express ignorance (leave it blank), you can express different intensities of preferences (vote Alice=100, Bob=90, and Hitler=0), you can express equality (make the numbers equal), and you get all this expressiveness very simply.
The US constitution was written in 1787 and ratified along with the Bill of Rights in 1791. It nowhere says that a "vote" has to consist of "the name of exactly one candidate, then shut up." In fact it nowhere defines "vote," although it mentions votes about 20 times.
The constitution is rife with such ambiguities and that was usually intentional. We at the Center for Range Voting believe that it was also intentional in this case: the authors of the constitution intentionally wanted to allow other kinds of voting than just plurality voting; they knew there were other kinds of voting and intentionally chose not to forbid them; and they intentionally remained agnostic on the question of what kind of voting system to use.
Why do we say that? Because we know that Thomas Jefferson, Edmund Randolph, and James Madison all owned copies of Condorcet's book! In fact Jefferson bought copies of everything by Condorcet he could get his hands on, and in at least one case, he annotated his copy, and he was so enthusiastic that he sent copies to Randolph and Madison. We also know that John Adams was familiar with the mechanisms used by the Venetians. This all happened before constitutional ratification in 1791. And we know that Benjamin Franklin apparently knew Condorcet personally (both were high in the French Academy of Sciences) and indeed Condorcet gave a warm elogy for Franklin upon the latter's death. And, Jefferson knew Borda too, since he mentioned him in a letter he wrote, and both Jefferson and Adams "met Condorcet on several occasions." (Also Borda was a military hero in the American Revolution.)
So while perhaps Jefferson et al did not fully follow Condorcet's mathematically intricate arguments, it is absolutely inconceivable that they did not grasp his fundamental starting point that rank-ordering-type votes were to be used in his (and Borda's) voting systems. And it also is absolutely inconceivable that they did not realize that there was an acrimonious conflict between Condorcet and Borda over whose voting system was better, i.e. they realized the question of which voting system was best, was not a trivial one and the answer was not clear.
And other voting systems besides plurality have already been used for various state governor and other high positions at various times and places throughout US history. The cumulative system used to be used in Illinois to elect representatives; it involved votes which were integer vectors summing to a constant (your vote could express opinions about more than one candidate in this system). The Bucklin system was used in various state primary and mayoral elections in the early 1900s. It involved rank-ordering (Borda-style) votes. We don't recommend those two systems, but they make it clear there is plenty of precedent in US history for other kinds of votes!
(See this for more discussion of the US Constitution and its authors' views on voting.)Iain McLean: The Political Economy of the French and American Enlightenments: Jefferson in Paris 1785-9, Oxford University and Yale University press 2001.
Iain McLean & A. B. Urken: Did Jefferson or Madison understand Condorcet's theory of social choice, Public Choice 73 (1992) 445-457.