Regional jet flight crew in cruise received a master warning BAGG SMOKE on EICAS; after running the checklist; the EICAS message extinguished however the illuminated button remained. Flight crew elected to declare an emergency and divert to an enroute airport.

Narrative

While enroute to ZZZ1 we had a master warning BAGG SMOKE on EICAS; and the associated triple chime as well as an illuminated BAGG EXTNG button. Commencing the memory items for BAGG SMOKE; the EICAS message extinguished; and the triple chime silenced. The BAGG EXTNG button however; was still illuminated. Being that the BAGG SMOKE message was not being displayed on the EICAS; we did not press the BAGG EXTNG button. We ran the procedure for the BAGG SMOKE. As per the procedure the Flight Attendant was asked to visually inspect the cargo compartment; and saw no smoke or fire indication through the inspection hole. We then advised ATC of our situation; and declared an emergency. We attempted to contact Dispatch; but were unsuccessful. At this point we decided that ZZZ was the nearest suitable airport; and advised ATC of our intention to divert into ZZZ. Once under way to ZZZ; We were able to communicate with dispatch through ACARS; and we made our intentions known. Once on he ground in ZZZ; we were met by CFR; once we were clear of the runway. After opening and inspecting the cargo compartment; they advised us on no sign of fire or smoke in the compartment. We then taxied into the gate. We contacted maintenance numerous times; however; maintenance personnel did not show up; until sometime after all passengers were de-planed. Twenty or so minutes later we proceeded to a spare aircraft on an adjacent gate.