A topology control algorithm can be applied to wireless sensor networks to construct a virtual backbone for maintaining network connectivity. For handling node failure, previous algorithms typically prefer to have redundant nodes so the power efficiency was compromised. This paper describes a Power-CDS (P-CDS) mechanism that schedules active and backup sensor nodes in the backbone for tolerating failures. When node failure is detected, both active and backup nodes will adjust their transmission ranges to maintain connectivity. Simulation results show that P-CDS forms a smaller connected dominating set than the other faulttolerant topology control algorithm. P-CDS also provides efficient broadcast with relatively low energy consumption.