Campaign spokeswoman Jen Psaki told reporters aboard Air Force One en route to a day of campaigning by President Obama in Texas the commercial highlights "whether Mitt Romney paid his fair share in taxes."
"As we know, until he releases more years of tax returns we're not going to have additional information on why he had investments in the Cayman Islands, why he had investments in a company in Bermuda, and what decisions he was involved in."
Romney has released his 2010 federal tax return and has said he will release 2011 eventually. But despite pressure from within his own party, he has resisted releasing any earlier returns.
"The ad raises the question that we won't know [whether Romney paid his fair share of taxes or hid income], and it's not possible for anyone to know, until he releases further years of tax returns and everybody is able to examine what is included in them," Psaki said.
Obama arrived in San Antonio for the first of four campaign appearances at 11:15 a.m. CDT and was greeted by "Desperate Housewives" actress Eva Longoria, among others. Supporters brandished signs reading "Keep hope alive, support the president" and "President Obama cares" outside the Henry B. Gonzalez Convention Center.
Notable deaths of 2014 [PHOTOS]