WASHINGTON  More than four decades after the surgeon general declared smoking a health hazard, the Senate on Thursday cleared the final hurdle to empowering federal officials to regulate cigarettes and other forms of tobacco for the first time.

The legislation, which the White House said President Obama would sign as soon as it reached his desk, will enable the Food and Drug Administration to impose potentially strict new controls on the making and marketing of products that eventually kill half their regular users. The House, which passed a similar bill in April, may vote on the Senate version as soon as Friday.

“This is a historic step changing the nature of tobacco in society forever,” said Clifford E. Douglas, the director of the University of Michigan Tobacco Research Network, which has extensively studied the health effects of smoking and was one of many groups that have long pushed for tobacco regulation.

The Congressional Budget Office has estimated the new law would reduce youth smoking by 11 percent and adult smoking by 2 percent over the next decade, in addition to reductions already achieved through other actions, like higher taxes and smoke-free indoor space laws.