President Barack Obama's plans to overhaul the American health care system received a boost on Wednesday when a second Republican senator indicated that she may support the legislation.

President Obama speaks at a rally on health care reform at the University of Maryland Photo: AP

Susan Collins joined fellow moderate Republican senator Olympia Snowe, in endorsing the goal of far-reaching changes in the US health care system.

The proposals to overhaul of the $2.6 trillion (£1.6 trillion) system were passed by the Senate Finance Committee, setting the stage for a major battle on the Senate floor itself.