Senate Majority Leader Harry Reid is calling on Republican presidential nominee Mitt Romney to release several more years of his tax returns, but did not repeat the unfounded claim that Romney hasn't paid income taxes for years.

Reid spoke Tuesday at the Democratic National Convention. On taxes, he described Romney as the biggest proponent of a rigged game for the wealthy.

He said looking at the one tax return that Romney has released shows why he is reluctant to release more, claiming that Romney chose Swiss bank accounts and Cayman Island tax shelters over American institutions. He said that Romney should release 12 years of tax returns like his father did when running for office.

Romney has said he would release a second year of tax returns before the election.