Gills are currently five points clear and on Saturday had a near full house of 8,500 at Priestfield.
With his team flying, Allen can only see more and more fans flooding in.
"We have a massive catchment area and the atmosphere when you are in here, in that technical area, is brilliant," Allen told the Kent Messenger.
"You can imagine what it's going to be like over the next few months when we get closer and closer to the special line. It's going to take off and it's going to be great.
"The supporters are the sales people if the players and our squad do our stuff week in, week out.
"They are the people in your shirt. And then they go to work. They tell the people at work and might go to the pub and tell them and on Sunday mornings the kids might tell their mates and at school they can be proud to be a Gillingham supporter."