360 Networks offers an aggregated T1 service. Recently, 360 Networks expanded the number of wire centers that the service offers.
"360networks, a facilities-based wholesale provider of telecommunications services, today announced the expansion of its Single Point of Interconnection (SPI) T1 service to an additional 758 wire centers..... SPI service now covers 2,194 wire centers in over 30 tier 1 to 4 markets within 19 states." [telecompetitor]
360 has an interactive map here. Also, 360 offers VoIP TN service too. It's network extends from Dallas to the west. It has a dark route from Dallas to New Orleans up to Memphis to Chicago.