Creating Bridge in Wireless Network

Is this even possible??

Here is what I have to do:

I have all my modem/wireless router downstairs and I work in an upstairs office. My office is remote office tied to another company in another physical location. They just purchased an IP phone for me to hook up to my internet to use so that when the phone rings in the office it rings here. The problem is NOT hooking the the ip phone, but getting internet upstairs without having another cable wire run from the cable company and an additional wireless router.

I am wondering if I can use one of the devices I have already at home to bridge my internet connection so that I can plug this ip phone in upstairs.

Here is the equipment I have:

Motorola Router
NetGear Wireless Router hooked to it ALL DOWNSTAIRS

I have an old Verizon DSL Wireless Router that has four open ethernet ports on the back. Is there anyway to use this router as a bridge to my internet connection downstairs and then plug the ip phone directly into it?

If so, HOW? I've read online somewhere I need to clone the MAC address. If anyone can help me that would be great.

I didn't have the money to purchase something else, I just wanted to know if I could get this to work