  We study the scenario of fermionic dark matter that annihilates to standard
model fermions through an s-channel axial vector mediator. We point out that
the well-known chirality suppression of the annihilation cross section can be
alleviated by s-channel internal Higgsstrahlung. The shapes of the cosmic ray
spectra are identical to that of t-channel internal Higgsstrahlung in the limit
of a heavy mediating particle. Unlike the general case of t-channel
bremsstrahlung, s-channel Higgsstrahlung can be the dominant annihilation
process even for Dirac dark matter. Since the s-channel mediator can be a
standard model singlet, collider searches for the mediator are easily
circumvented.
