RICHARD TUCK WANTS TO SHOW THAT it is rational to vote.1 Mancur Olson argued that it is irrational to vote because individual votes have little or no causal power over electoral outcomes. Tuck wants to prove that Olson is mistaken. Tuck argues some votes are causally efficacious. However, even if Tuck succeeds in showing that some votes are causally efficacious, all this does is undermine part of Olson’s worry about whether voting is instrumentally rational. Showing that votes are causally ef- ficacious is not sufficient to show that voting is rational. Tuck fails to show that it is rational to vote except in unusual cases.