  We present a new survey for CO in dwarf galaxies using the Kitt Peak 12m
telescope. We observed the central regions of 121 northern dwarfs with IRAS
detections and no known CO emission. We detect CO in 28 of these galaxies and
marginally detect another 16, increasing by about 50% the number of such
galaxies known to have significant CO emission. The galaxies we detect are
comparable in mass to the LMC, although somewhat brighter in CO and fainter in
the FIR. Within dwarfs, we find that the CO luminosity, L_CO, is most strongly
correlated with the K-band and the far infrared luminosities. There are also
strong correlations with the radio continuum and B-band luminosities, and
linear diameter. We suggest that L_CO and L_K correlate well because the
stellar component of a galaxy dominates the midplane gravitational field and
thus sets the pressure of the atomic gas, which controls the formation of H_2
from HI. We compare our sample with more massive galaxies and find that dwarfs
and large galaxies obey the same relationship between CO and the 1.4 GHz radio
continuum (RC) surface brightness. This relationship is well described by a
Schmidt Law with Sigma_RC proportional to Sigma_CO^1.3. Therefore, dwarf
galaxies and large spirals exhibit the same relationship between molecular gas
and star formation rate (SFR). We find that this result is robust to moderate
changes in the RC-to-SFR and CO-to-H_2 conversion factors. Our data appear to
be inconsistent with large (order of magnitude) variations in the CO-to-H_2
conversion factor in the star forming molecular gas. [abridged]

Astrophysics