Top Democrats in New Hampshire and Massachusetts are ripping former Gov. Mitt Romney’s record on job creation, pointing to a series of disquieting statistics about the Massachusetts economy while Romney was at that state’s helm.

Romney’s business experience “suggested he would be good at job creation, when in fact he was terrible at it,” said John Walsh, Democratic party chairman of Massachusetts, on a conference call with reporters Monday. (Michele Bachmann officially enters 2012 race)

Walsh pointed to one statistic in particular: during Romney’s tenure as Massachusetts governor his state was 47th out of 50 states in terms of jobs created nationwide, according to the Labor Department.

That statistic has become a mantra of top Democrats, including David Axelrod and Debbie Wasserman Schultz, their most potent weapon in the early stages of a war to define Romney on the economy.

Because of Romney’s success in business – he founded venture capital firm Bain Capital on $37 million in seed money in 1984, turning that into billions of dollars as he increased profits at scores of businesses – the economy is his strength as a political issue.

Known for his ability to turn around businesses that were headed south, Romney also rescued the Salt Lake City Olympics from a bribery scandal that almost resulted in the winter games being called off that year.

But Democrats have been able to turn the economy into a weakness of Romney’s in past elections, most notably in 1994 when Romney lost a bid to unseat the late Sen. Ted Kennedy.

Back then Kennedy organized striking workers from a business recently purchased by Bain Capital to attend Romney’s campaign events, transforming the public’s view of Romney from skilled executive into the heartless number-cruncher who decides that you are fired.

In an election cycle in which unemployment remains stuck around 9 percent, the battle over Romney’s economic track record could be pivotal to who wins the presidency — if Romney survives the GOP primary, of course.

Meanwhile, Romney is in New Hampshire campaigning and has relentlessly attacked President Obama over the poor economy during his first three years as president.

“What this president has done, has slowed the economy. He didn’t create the recession, but he made it worse, and longer,” Romney said at the June 14 debate in New Hampshire.

Romney’s spokeswoman, Andrea Saul, responded to the Democratic attacks by unloading on Obama’s economic record and saying the criticisms were an attempt to distract from it.

“Barack Obama’s record on job creation is shameful. Under his watch, America has lost roughly 2.5 million jobs,” she said, “Democrats will spend the next 17 months trying to distract the American people from President Obama’s horrible jobs record, and it’s not going to work.”

But she also provided an affirmative defense of Romney’s record, saying there were markedly more jobs created in Massachusetts during Romney’s tenure as governor than during the governorships of his predecessor and successor.

“Mitt Romney created nearly 50,000 jobs as governor of Massachusetts and led his state to one of the most dramatic job market turnarounds in the country,” Saul said.

During Republican Gov. Jane Swift’s tenure, from 2001 to 2003, 62,663 jobs were lost. During Gov. Deval Patrick’s tenure, 73,001 jobs have been lost.

But the Democratic attack is about Massachusetts’ record in comparison with other states. The comparison is important because national and even global economic trends affect a given state’s economy more than the actions of a governor.

The fact-checking website Politifact.com called the Democratic attacks “half true” because “we found little evidence to support…that Romney is responsible for those jobs numbers. Economists told us that it’s a stretch to blame or credit Romney or any governor for job numbers.”