What's the easiest way to stack bus route labels like this?

[Dan_DMR]

I'd like to be able to label bus route numbers over the route polylines similarly to what's shown in this example image. Is there a way to do this without converting the labels to graphics or bringing them into another program like illustrator? Would have though Maplex has something to do this quickly. Thanks 

[jcarlson]

Are these labels coming from separate features? I've seen this kind of labeling work in situations where each segment participates in one to many routes, rather than having a line per route. Otherwise, I think you'll need to adjust them by hand.

[Dan_DMR]

Yeah each bus route has its own feature (although there are at least 2 features per bus route # to account for inbound and outbound patterns)