We construct a phenomenological model of electroweak-scale inflation that is inaccordance with recent cosmic microwave background observations by WMAP, whilesetting the stage for a zero-temperature electroweak transition as assumed in recentmodels of baryogenesis. We find that the scalar spectral index especially poses tightconstraints for low-scale inflation models. The inflaton–Higgs coupling leads tosubstantial mixing of the scalar degrees of freedom. Two types of scalar particleemerge with decay widths similar to that of the Standard Model Higgs particle.