More than a half-million unemployed workers in Ohio and several other states are missing out on weeks of additional money because of the way laws in their states are written.

Changing the laws would enable roughly 540,000 unemployed workers to qualify for 13 to 20 weeks of extended federal benefits after they’ve exhausted their state and emergency federal benefits, according to the National Employment Law Project. Without the change, workers whose federal benefits run out this month or next month could be left without any payments in the midst of a worsening job market.

Under the federal economic stimulus package, the federal government will pick up 100 percent of the tab for the extended benefits. Normally, the cost is split between the states and the federal government.

There are two ways in which states with high unemployment rates can qualify for extended benefits. Under one, a state can qualify if the number of people receiving state unemployment payments is more than 5 percent of the number of employed workers in the state. This typically has been the more difficult threshold for states to reach, yet several still have laws requiring them to follow this method.

It’s likely that Ohio — currently at 4.5 percent — and other states hit particularly hard by the economy eventually will meet that threshold. But thousands of workers still could be left without assistance until that happens, according to the law project, which advocates policies and programs that benefit workers.

A second method available to states to qualify has a threshold easier to meet. A state also can qualify for extended federal benefits if its unemployment rate is above 6.5 percent for three consecutive months. Just 11 states with high unemployment rates have this option written into their laws.

Ohio’s unemployment rate is 9.4 percent, and it is among the 13 states, plus the District of Columbia, that would qualify for the program now if it adopted the latter method.

“I don’t see why Ohio doesn’t jump on this,” said Karl Schafer of West Liberty, Ohio, who was laid off from his manufacturing job at Navistar in October 2007. “Look, nothing is coming out of our pocket. Let’s get this done to help out the unemployed.”

Schafer, who has a wife and three children, said his emergency federal benefits will run out in mid-April. He wrote all Democratic state House representatives, as well as Rep. David Burke, the Republican who represents his district, asking them to change the law.

Gov. Ted Strickland has begun conversations about the change with legislative leadership, said spokeswoman Amanda Wurst.

“He believes it’s a common sense and necessary change,” Wurst said. “The governor’s approach is to maximize all federal recovery act resources to maximize the benefit to Ohioans.”

The other states missing out on extended benefits for their unemployed workers are Alabama, Arizona, California, Florida, Georgia, Illinois, Kentucky, Maine, Mississippi, Missouri, New York, Ohio and Tennessee.

A few states with Republican governors, such as Louisiana, have balked at changing their state unemployment benefits laws to receive more federal stimulus money. They have said that increasing the amount of the benefits, or enabling more workers to become eligible, will place an additional burden on the state in future years.

The National Employment Law Project said states making changes in their laws to receive extended federal benefits can include a clause that erases the change at the end of the year. The federal stimulus package only requires the federal government to pay 100 percent of the benefits through the end of this year.