In a new television ad, President Obama shifts from attacking Mitt Romney’s business experience to attacking his political career.

“Heard it Before” attacks Romney’s record as governor of Massachusetts, arguing that his job-creation claims are empty.

Romney had “one of the worst economic records in the country,” the narrator of the spot says. After a clip of Romney from his gubernatorial campaign saying “I know how jobs are created” is played, the narrator adds: “Romney economics: It didn’t work then and it won’t work now.

Of the commercial, Romney spokeswoman Andrea Saul said: “Having abandoned ‘Hope and Change,’ the Obama campaign only ‘Hopes To Change The Subject’ from an abysmal jobs report.”

As the ad highlights, Massachusetts was ranked 47th out of 50th in job growth during Romney’s tenure. He did turn around a negative employment trend, but other states grew faster. The former governor argues that he inherited a manufacturing and tech boom boost and helped put the state back on the right track. (It’s hard to say; Romney stepped down in early 2007 and jobs began falling again when the recession hit in mid-2008.)

The ad continues an Obama campaign offensive that began last week with a memo and web video about Romney’s tenure. Senior Obama strategist David Axelrod also held a press conference in Boston to highlight Romney’s record as governor.

The shift away from controversial criticisms of Romney’s work at Bain Capital will be cast by some as an abandonment of that line of attack. But Obama’s team has argued that Bain and Romney’s time as governor are part of the same message: Romney has spent his time protecting the wealthy at the expense of the average person.

“Heard it Before” is airing in Colorado, Florida, Iowa, North Carolina, New Hampshire, Nevada, Ohio, Pennsylvania, and Virginia in what the campaign says is a “significant” buy.