yes, if you keep your most light-needy corals directly under the halide, and partially up the rockwork for some acros.
a 37 gallon is 30" across if i'm not mistaken. i have a single 250 watt halide over a 40 breeder, which is 36", and it works fine. i just keep the acros towards the middle and the softies/lps towards the outer edges.
and- pick a high quality bulb, ballast, and reflector.