Ryan Murphy and Brad Falcuk’s new FX drama series American Horror Story launched with 3.2 million viewers and 2 million adults 18-49 at 10 PM last night. It matched the premiere demo rating of Murphy’s previous FX series, the hit Nip/Tuck, and was up 33% from the series debut of FX’s current flagship drama Sons of Anarchy (1.5 million). It is running behind the all-time FX champ — the series premiere of FX’s signature cop drama The Shield, which collared 3.2 million viewers in 18-49 — but that might change, according to FX president and general manager John Landgraf. “We’re really thrilled by the premiere ratings performance of American Horror Story,” he said.  “We know that when the Live+7 ratings come in, that of the 13 drama series FX has premiered, AHS will rank at least No. 2 all-time in adults 18-49 behind The Shield, and there is a possibility that it could be our highest ever.” Landgraf also noted the spike in social media traffic triggered by the AHS premiere. For its premiere night, including two encores, AHS averaged 5 million viewers, 3.2 million of them in the adults 18-49 demo.