As with any DC circuit, voltage drop occurs with distance, the question is whether there is enough cable length to cause a problem.
If the maintenance programming is trying to keep the battery at some voltage (12.7?), but you have a couple of tenths worth of voltage drop, then the maintainer will (try?) to charge at it's designed voltage but the battery will be at a higher voltage?
Should be very easy to test. Hook up maintainer at battery, check voltage (make certain it's actually in its cycle), then hook up at the under hood post locations and check voltage at posts, and then again at battery.
If you're using a quality DMM, you'll easily see a difference. Then it's just a matter of determining if the drop is inside or outside of the maintenance range.