Power utilization in an efficient manner is a hot research issue in wireless sensor networks (WSNs). WSNs consist of energy hungry sensor nodes. Researchers have been trying to increase the lifetime of WSN since the development of WSN technology. Dynamic Transmission Power Control (DTPC) is a method for an efficient utilization of the energy resource and thus leads to an increase in lifetime. It has been used for the determination of minimum transmission power. A valuable study about the impact of variable transmission power on link quality has already been present in literature. In contrast to DTPC, transmitting data at a 100 percent power level may guarantee successful data delivery but it may leads to a rapid decrease in battery power level. In addition, the interference is likely to occur. In DTPC the transmission range of each node is different from other and adjusted according to the current topology of the network. In this paper, network connectivity is the major factor in adjusting the transmission range of these nodes rather than RSSI. In this work, for the sake of saving power and increasing the system lifetime, DTPC is being used in conjunction with GRACE, a well known power-aware routing protocol in literature. The resulting routing protocol leads to greater network lifetime. Simulation results show an apparent improvement as compare to the simple GRACE routing protocol.