Some googling shows typical dishwasher circulation impeller pumps drawing about 60-90 Watts.
That’s actually surprisingly low. Turn off a few lights and you’ve offset the dishwasher pump.
Better than estimating (over or under) is measuring. I just ran a normal load of dishes through my (almost) brand new Bosch 300 series dishwasher I installed 2 weeks ago.
Plugging the dishwasher into an EM100 energy meter I got the following data:
Total run time: 2:16:42
Max wattage: 1,184W
Max Amps: 10.14A
Power used: 0.7 KWh
Based on my most recent power bill I’m currently paying 7.69 cents per KWh. So that load of dishes cost me 5.38 cents in electricity. Others can do some calculations with these numbers and make analogies from them, but to me a nickel’s worth of power is indeed negligible.