The United Federation of Planets spanned thousands of light years and had over 150 member planets across the Alpha and Beta quadrants. For the purpose of this question, I'm considering the following to be important traits of the Federation.
Territory (managed by a government or quasi-governmental group) spread across multiple planetary systems.
Member planets willingly joined and contribute resources to the group. Members are from multiple species, each with their own original cultures and languages.
Primarily interested in peaceful exploration, science, and free trade.
Powerful: Technologically able to fend off any of their less-peaceful neighbors and defend their territory when necessary.
With these qualities in mind, is there something resembling the Federation in the Delta quadrant, around the time of Voyager? I didn't watch all of Voyager, but the Delta quadrant always seemed like a vast and desolate wasteland, with independent systems here and there, and the occasional violent predatory group attacking them.
The part about "multiple species and cultures" is optional, but does speak to a Federation-like mentality of peaceful cooperation. Sadly I suspect the Borg have prevented most multi-planetary civilizations from growing too powerful.