Outbound campaign stuck in queue

[Anonymous]

I've got preflight emails going to a small testing list of 5 members. Usually these are sent immediately, but three of them have been stuck for some time. At nearly 1 pm GMT, the message being shown is still : 
 

This campaign was initiated at 24 November 2014 09:58 GMT and is preparing leads for processing 

What might be causing this? Is there anything I can do to speed it up? 

Edited:  Also, I have one that isn't using the testing list, it's just set up to go directly to 2 email addresses, and that one is stuck also. Sample emails are not affected, they get sent immediately as expected. 

[Anonymous]

Update: just like waiting for a red bus in London, suddenly all three turned up. I guess something was stuck in the queue, but it magically fixed itself. 

Or if someone in Support gave it a kick, thank you. 🙂

[Anonymous]

Hi Kathleen,

How long did you end up waiting? I'm having the same issue, and my campaign was created 2 hours ago.

Just opened a case with Marketo.

Carolyn