We present an analysis of the temperature dependence of the optical re
sponse of small sodium clusters in a temperature range bracketing the
melting phase transition. When the temperature increases, the mean exc
itation energy undergoes a red-shift and the plasmon is significantly
broadened, in agreement with recent experimental data. Due to large th
ermal size and shape fluctuations the single-particle levels acquire a
prominent width. We also predict a sharp increase of the static polar
izability with temperature.