WASHINGTON (AP) — A new independent study says Republican Mitt Romney's tax plan would increase taxes on low-income families while cutting taxes for the middle-class and the rich.

The study by the Tax Policy Center says, on average, households making less than $20,000 would see their taxes increase by more than 60 percent by letting tax cuts enacted under President Barack Obama expire. Those tax cuts target low-income families.

The study by the independent research group says people making more than $1 million would get tax cuts averaging 15 percent.

Romney, a former Massachusetts governor, is the front-runner for the GOP nomination for president. Campaign spokeswoman Andrea Saul said Romney's plan holds the line on tax rates for individuals and families and dramatically reduces the corporate tax rate to create jobs.