What does "on the spoke" mean?

Solution 1:

Knowing next to nothing about Halo, is the Spoke a place, perhaps? I don't have any audio here at work to check the teaser.

Edit: Aha! Following the link to the transcript, it's clear that the action is taking place on a Ring Habitat, a wheel-shaped space station. The tradition in SF is to use the same nomenclature for Ring Habitats as you would for a wheel, so the outer rim is connected to the central hub by spokes. "Reinforcements are on the spoke" therefore means "Master Chief is on (in?) the (a?) corridor between centre and the edge."

Solution 2:

I would rather go with "reinforcements are on the spot", but pronounced with a weird accent making it sound like "on the spoke".

"on the spot" would fit with the current situation, which calls for reinforcements:

• right here ("on the spot")
• right now ("right away", again "on the spot")

Solution 3:

"On the spoke" means "on the way".

"Wheeling around" or "wheeling in" is what they used to call folding the flanks in on a battlefield. Being "on the spoke" refers to the "wheeling in" of the flanks.