If I’ve only got one mic to dedicate to the drum kit, it’s likely going to be a condenser mic. This has happened more than once, I’ve had to produce live shows where the mixer only had 8 channels for the entire band – so having a single mic technique already that’s tried and tested is quite important. When using a single condenser mic for the drum kit, it all depends on the polar or pickup pattern. If the mic only has a cardioid pattern available, I’ll place it around 5 feet away from the kit about even with the cymbals, but angled down to capture some more of the tone from the kick and tom.
If the mic can work in a figure 8 polar pattern, you can place it in the kit area just above the kick drum. One side of the mic will pick up a nice powerful kick sound, and the other will pick up the cymbals above it. You’ll want a strong stand, and you’ll also probably have to adjust the mic a bit to really hone in on your balance. An omnidirectional condenser can go in the same spot, but perhaps a bit more equidistant from every element of the kit.
The Samson CL8a is a great choice for this as it has selectable polar patterns. You can try out all of the different configurations with one mic! Just be prepared to give a little boost to the low end on your EQ, or roll off a bit of highs. Condenser mics tend to be a bit more friendly to the upper sonic range.