Process for polymerizing fluoromonomer to form an aqueous dispersion of fluoropolymer particles including: (a) providing an aqueous medium in a polymerization reactor, (b) adding nucleating additive comprising polyalkylene oxide having a number average molecular weight of about 50 to about 2000 to the aqueous medium in an amount of about 0.1 ppm to about 50 ppm based on water in the aqueous medium, (c) exposing the nucleating additive to oxidizing agent to form a dispersion of oleophilic nucleation sites in the aqueous medium; (d) pressurizing the reactor by adding fluoromonomer, and (e) adding polymerization initiator to the aqueous medium to cause the polymerizing of the fluoromonomer to form fluoropolymer particles dispersed in the aqueous medium.