Mentally contrasting future with reality is a self-regulation strategy that triggers expectancy-dependent energization for tasks instrumental to attaining the desired future. Energization by mental contrasting even transfers to tasks unrelated to the desired future at hand. Would such energization transfer by mental contrasting even energize people to perform unrelated tasks for which they have low success expectations? In Laboratory Experiment 1, mentally contrasting (vs. indulging) about performing well in a creativity task triggered physiological energization and better performance in an unrelated low-expectancy cognitive task that participants received in place of the creativity task. In Field Experiment 2, mentally contrasting an interpersonal wish helped schoolchildren invest more effort and perform better in a low-expectancy academic task—finding typos. Online Experiment 3 replicated Experiment 2 with adults. Mental contrasting participants’ effort and performance in the low-expectancy academic task did not differ from their effort and performance in a high-expectancy task. We discuss implications for designing interventions to foster energization for low-expectancy tasks.