Akahma has a great point and I've definitely fallen into the trap of whitlisting too soon sometimes, but it might also be worth testing the campaign anyway because that's the only way you'll find out.
I just took this screenshot to show you that
Popads is saying the same thing to me right now about a campaign I've been running since the weekend:
But here are my stats for the last three days:
So "we have no traffic" is really misleading because I'm getting plenty.
The thing about the Popads traffic estimator is that it seems to be based on traffic
sales data (as explained on the Inventory page, per screenshot below):
What this seems to mean is that if you create a very targeted campaign then Popads might have no other advertisers with the same highly targeted settings, so they have no data to refer to in order to predict the traffic you could receive. This could mean there is no traffic, but it might also mean you're literally the only advertiser targeting the specific combination of settings.