The ad by the Log Cabin Republicans notes that Romney signed legislation in 2003 that increased taxes on New Hampshire residents who worked in Massachusetts. It also says Romney raised taxes on businesses, a point Romney disputes by saying he was merely closing tax loopholes.
"Mitt Flops - sounds like something you'd wear to the beach, but they could cost you," the ad states. "Let's see. Running for governor, Mitt Romney said he'd balance the budget without raising taxes. So what'd he really do? He raised taxes on some New Hampshire residents who worked in Massachusetts, taxing their income and their pensions."
The ad represents yet another anti-Romney campaign by an independent political group that is hitting the airwaves with six weeks before the New Hampshire primary. This weekend, the Republican Majority for Choice, a group that advocates abortion rights, is running television and newspaper ads in New Hampshire and Iowa accusing Romney of flip-flopping on abortion.
The radio ad represents the second effort by the Log Cabin Republicans to cast Romney as a flip-flopper. Last month, the group aired an ad in Iowa and on national cable that sought to undercut his support among social conservatives.
Romney spokesman Kevin Madden said it was no surprise that a gay rights group would oppose Romney because he has supported a federal amendment that would declare marriage to be between a man and a woman.
"This negative attack and gross distortion of the governor's record was launched and paid for by a group recognized as having Mayor (Rudy) Giuliani as their 'favorite' candidate," Madden said. Giuliani has had the support of some gay rights groups in the past and has backed limited legal recognition for same-sex couples.
"Governor Romney has a stellar record of fiscal responsibility, having cut wasteful spending and worked to lower taxes as a chief executive focused on pro-growth economic policies," Madden said.
The criticism from the Log Cabin Republicans is similar to criticism of Romney contained in Giuliani's Web site, and in some cases the two camps cite the same sources.
But Log Cabin President Patrick Sammon said there was no coordination between his group and the Giuliani camp.
"We are not endorsing any candidates in this race," he said. "We have members who are working and supporting different candidates. Gov. Romney is, as usual, trying to attack the messenger instead of responding to the message."