  We discuss renormalization of propagator of interacting Rarita--Schwinger
field. Spin-3/2 contribution after renormalization takes usual resonance form.
For non-leading spin-1/2 terms we found procedure, which guarantees absence of
poles in energy plane. The obtained renormalized propagator has one free
parameter and is a straight generalization of the famous free propagator of
Moldauer and Case. Application of this propagator for production of
$\Delta^{++}(1232)$ in $\pi^{+}\particle{p}\to \pi^{+}\particle{p}$ leads to
good description of total cross-section and to reasonable agreement with
results of partial wave analysis.
