  A new reentrant insulating phase (RIP) in low magnetic fields has been
reported in the literature in strongly interacting 2D carrier systems and was
suggested to be related to the formation of a Wigner crystal [e.g. Qiu et al,
PRL 108, 106404 (2012)]. We have studied the transformation between the
metallic liquid phase and the low field RIP in a dilute 2D hole system with
large interaction parameter $r_s$ (~20-30) in GaAs quantum wells. Instead of a
sharp transition, increasing density (or lowering $r_s$) drives the RIP into a
state where an incipient RIP coexists with the metallic 2D hole liquid. The
non-trivial temperature dependent resistivity and the in-plane magnetic field
induced enhancement of the RIP highlight the competition between two phases and
the essential role of spin in this mixture phase, and are consistent with the
Pomeranchuk effect in a mixture of Wigner crystal and Fermi liquid.
