The straight answer to your question is that this is not possible. There is one way that you can do this, but there are many dependencies. You can create a custom control that will be wrapper for a ContentView control. You need to bind this control to staged content and certain versions of IContent objects. This binding should be performed only when cmspagemode="preview" or you have to append a custom QueryString that will be used only when you want to see staged version of a content item.
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