  We report spectroscopic observations for 19 $\delta$\,Sct candidates observed
by the {\it Kepler} satellite both in long and short cadence mode. For all
these stars, by using spectral synthesis, we derive the effective temperature,
the surface gravity and the projected rotational velocity. An equivalent
spectral type classification has been also performed for all stars in the
sample. These determinations are fundamental for modelling the frequency
spectra that will be extracted from the {\it Kepler} data for asteroseismic
inference. For all the 19 stars, we present also periodograms obtained from
{\it Kepler} data. We find that all stars show peaks in both low-
($\gamma$\,Dor; g mode) and high-frequency ($\delta$\,Sct; p mode) regions.
Using the amplitudes and considering 5\,c/d as a boundary frequency, we
classified 3 stars as pure $\gamma$\,Dor, 4 as $\gamma$\,Dor\,-\,$\delta$\
hybrid, Sct, 5 as $\delta$\,Sct\,-\,$\gamma$\,Dor hybrid, and 6 as pure
$\delta$\,Sct. The only exception is the star KIC\,05296877 which we suggest
could be a binary.
