While it is fine to do so, the dinner party would then be considered less formal and more of the potluck variety, so keep that in mind when you’re planning the rest of the meal and decor. It is never acceptable to ask only one guest to bring an item. If guests are asked to bring a bottle of wine, it is expected that it will be served at the meal, as opposed to a hostess gift, which the hostess could choose to open at any point after the party.