Let my customers rank their submitted ideas

I can allow my customers to submit ideas, and provide some form of priority value they can set. However if they set some or all of the ideas to the same priority I cannot identify which is the most important idea of that set (from the point of view of that customer).

I want a way that customers, via the idea portal, can see a ranked list of the ideas they have submitted/voted for and change the ranked order of those ideas.

I know I can give my customers a number of votes and ask them to give the most votes to the idea they consider most important, but that is less intuitive and harder to manager for the customers. A drag and drop list of ideas that they can choose the order for is much simpler and intuitive.

I would then want a way to identify the rank of each idea, so we can focus on those that are ranked the highest across our customers.