COUNTIFS with a range of values for criteria

I need to use the COUNTIFS function in this manner:

I have three items I want to look at and if all three match, then count it. However, the third criteria is any item from a list.

Criteria1 = Account Manager Name
Criteria2 = Forecast Stage
Criteria3 = Campaign1 or Campaign2 or Campaign3, etc.

The first two criteria are easy, but the third one is more difficult. Any marketing campaign on a list I created on another sheet will satisfy the criteria. I will probably add items to the list in the future, so I don't want to hard code it.

Any suggestions?

The drop down list doesn't work because even though it is a list, there can only be one item in that cell. I need it to pass the criteria if it matches ANY of the campaign names, not just a single value.

Thanks for the reply, Any other suggestions?