ntiff eventually will have to establish jurisdiction by a preponderance of the evidence, either at trial or at a pretrial evidentiary hearing. See CutCo Industries, Inc. v. Naughton, 806 F.2d 361, 365 (2d Cir. 1986); Marine Midland Bank, N.A. v. Miller, 664 F.2d 889, 904 (2d Cir. 1981). But at this stage, prior to d