In a Cardinal Rating (CR) system, each voter rates each candidate on a numerical scale such as zero to ten, and the candidate with the largest accumulated total wins. The simplest form of CR is called Approval Voting: the effective rating scale is simply zero and one. Approval Voting is much easier to implement than general CR, but a simple analysis shows that it is "strategically equivalent."
To understand why, consider first a CR election with two candidates and a rating scale of zero to ten. Why would anyone rate the candidates anything other than zero and ten? Any other combination only diminishes the effect of the vote, which is obviously never a good strategy. So the best strategy in the two-candidate case is to give one candidate the minimum rating and give the other the maximum.
With more than two candidates, the same principle still applies. For any possible pair of candidates, the only advantage a vote gives to one over the other is determined by the difference in their ratings. If a voter decides to specify a preference for one over the other, the best strategy is never to voluntarily diminish the effect of the vote with regard to that preference. Minimum and maximum ratings are therefore still the best strategy.
Approval Voting is a special case of CR that only allows minimum and maximum ratings. It suffers no significant disadvantage compared to general CR, and it is much easier to implement. Approval voting also goes a long way toward overcoming the "lesser of two evils" problem inherent in our current plurality system, which artificially entrenches our political system into a two-party duopoly without effective competition from other parties.
See for yourself! Vote and compare the results: