BOSTON (AP) -- Mitt Romney is trying to gain an edge in the presidential contest with the disputed charge that President Barack Obama is giving welfare recipients a free ride.

To sharpen that argument, Romney points to a record of pushing for tighter welfare rules during his four years as Massachusetts governor, including requiring single parents with children as young as a year old to work in return for benefits.

Romney also opposed allowing time spent in job training or education programs to count toward the state's 20-hour work requirement and urged the state to adopt a five-year lifetime limit on welfare benefits.

Romney's camp hopes to draw a sharp contrast with Obama on welfare, but his campaign has come under scrutiny for what Democrats and many independent fact-checkers say are dubious charges.