By Ros Krasny
DURHAM, New Hampshire (Reuters) - Former President Bill Clinton took to the campaign trail in New Hampshire on Wednesday, lending President Barack Obama some firepower in a battleground state that has recently warmed to the idea of a second term for the incumbent.
Hours before Obama takes on Republican challenger Mitt Romney in Denver in the pair's first nationally televised debate, the 42nd U.S. President fired up a rally at the University of New Hampshire-Durham.
Clinton cast a positive light on Obama's economic record, drew sharp policy differences with Romney, and highlighted what he suggested was a tilt by the Republican Party away from policies that had been reliably bipartisan for decades.
"The Tea Party strangled the Republican Party so much that oxygen stopped going to the brain," Clinton told the standing-room-only crowd, estimated at 1,675, in the college gymnasium.
Clinton struck similar notes to his speech at the Democratic Convention in Charlotte in August and drew sharp distinctions between Obama and Romney on the issues of student loans, health care, the 2008 auto bailout, and tax policy.
"Trickle down economics doesn't work. It doesn't add up. Arithmetic works better," he said.
He also jabbed Romney's comment, made at a fundraiser in Florida and secretly recorded, about the "47 percent" of Americans who do not pay federal income taxes and were dependent on the government.
"The guy with a tax account in the Cayman Islands is attacking other people for not wanting to pay income tax? I mean, you've got to give him credit," Clinton said.
New Hampshire and Clinton go back a long way. A surprise second place finish in the state's 1992 Democratic primary helped revive the flailing presidential bid of the then little-known Arkansas governor.
Clinton went on to win New Hampshire in the 1992 general election. Since then the state, long a Republican stronghold, has voted Democratic in each presidential election except 2000. Obama won the state by 9 points in 2008.
But a sour economic recovery has held New Hampshire in the undecided column most of the year.
Although the state's labor market and housing market are strong relative to national averages, "New Hampshire's growth performance thus far in 2012 can be labeled shaky at best," said economists at IHS Global Insight in Lexington, Massachusetts.
In a pattern similar to battleground states such as Ohio and Florida, some surveys show Obama has opened a sizable lead over Romney in New Hampshire in recent weeks.
Romney, the former governor of neighboring Massachusetts, has a luxury vacation home in Wolfeboro on Lake Winnipesaukee in central New Hampshire.
The latest Granite State poll conducted by the UNH Survey Center showed Obama up by 15 points, 52 percent to 37 percent, with 9 percent still undecided. Obama has an edge among independents, and a wide lead with women voters.
The survey of 600 likely general election voters was conducted by landline and cellular telephone on September 27-30, and had a margin of error of plus or minus 3.9 percent.
Overall, the Reuters/Ipsos daily tracking poll on Wednesday showed Obama up among likely voters by 47-41 percent.
(Reporting By Ros Krasny; Editing by Vicki Allen)