Senate Majority Leader Harry Reid (D-Nev.) said on Thursday that Mitt Romney gives "used car salesman a bad name."
He made his remarks in Las Vegas, during his introduction of Vice President Biden, who was campaigning there.
"Now, Joe Biden stands for everything that's fair and honest — he's a man of integrity. The man that's leading the Republican ticket for president of the United States is giving used car salesmen a bad name," Reid said in his remarks introducing Biden. "Think about it for a minute: Have you ever seen anyone that would do anything, say anything like Mitt Romney?
Reid has been a vocal critic of the GOP nominee. Earlier in the campaign he claimed Romney didn't pay taxes, a charge the Romney team refuted.
Biden's stump speech in Las Vegas, Nev., included much of the same points of previous speeches. He warned that abortion laws that came from the Supreme Court ruling of Roe v. Wade wouldn't survive a Romney administration.
He also criticized Republicans who signed Americans for Tax Reform president Grover Norquist's pledge not to raise taxes.
"All those Republicans signed a pledge saying 'we will not ask one thin dime more from millionaires,'" Biden said. "We promise you we will not in any way raise revenue from them. We will not raise taxes at all on anybody period. Instead of signing a pledge to Grover Norquist, they should sign a pledge to the middle class. They should sign a pledge saying 'we're gonna level the playing field. We're going to give you a fair shot again.' "
A spokeswoman for the Republican National Committee said Reid's comment is a sign Democrats are on "defense."
"Any time Team Obama has to send Harry Reid out you know they are on defense. Without a second term agenda, President Obama’s campaign is resorting to negative attacks," RNC spokeswoman Kirsten Kukowski wrote in a statement.
—This story was updated at 6:31 p.m.