  The transition in quantum chromodynamics (QCD) from hadronic matter to the
quark-gluon plasma (QGP) at high temperatures and/or net-baryon densities is
associated with the restoration of chiral symmetry and can be investigated in
the laboratory via heavy-ion collisions. We study this chiral transition within
the functional renormalization group (FRG) approach applied to the two-flavor
version of the extended Linear Sigma Model (eLSM). The eLSM is an effective
model for the strong interaction and features besides scalar and pseudoscalar
degrees of freedom also vector and axial- vector mesons. We discuss the impact
of the quark masses and the axial anomaly on the order of the chiral
transition. We also confirm the degeneracy of the masses of chiral partners
above the transition temperature. We find that the mass of the $a_1$ meson
($\rho$ meson) decreases (increases) towards the chiral transition.
