* Reuters/Ipsos poll says Obama increased lead over Romney
* Ad buy-tracking firm: 72 pct of spending for negative ads
By Sam Youngman and Jeff Mason
DES MOINES/DENVER, Aug 8 (Reuters) - President Barack Obama and his Republican rival Mitt Romney traded barbs over welfare and women’s rights from the campaign trail on Wednesday, each seeking an edge in critical states that could tip the Nov. 6 election result.
Romney told supporters in drought-hit Iowa that their state felt like a “second home.” He gave a blistering speech accusing the Democratic president of loosening work requirements in a 1996 welfare law and warned that a second Obama term would lead to “chronic high levels of unemployment as far as the eye can see.”
“It’s tough to be middle class in America today,” Romney told an enthusiastic crowd at Des Moines’ Central High School, later visiting a cornfield to show support for farmers coping with the drought across the Midwest.
Obama, meanwhile, launched a two-day campaign swing in Colorado with an eye on women voters, another key constituency in what is likely to be a close election hinging on battleground states including Iowa, Colorado, Ohio, Florida and Virginia.
“He will focus his remarks on his commitment to ensuring women have access to affordable health care, to make choices about their healthcare decisions,” Obama campaign spokeswoman Jen Psaki told reporters aboard Air Force One.
Sandra Fluke, the Georgetown University Law student who conservative talk-show host Rush Limbaugh called a “slut” for her outspoken support of Obama’s contraception coverage policy, is set to introduce the president at his first event in Denver.
A Reuters/Ipsos poll released on Wednesday showed Obama’s lead over Romney among registered voters at 49 percent to 42 percent, up slightly from the 6-point advantage the president held a month earlier over the former Massachusetts governor.
Separately, an ABC News/Washington Post poll showed 49 percent of Americans view Romney unfavorably, compared to 43 percent of voters who gave Obama unfavorable marks.
And the latest poll from Quinnipiac University, CBS and the New York Times showed Obama ahead of Romney in Virginia and Wisconsin but trailing the Republican contender in Colorado.
Psaki said the Obama campaign expected a tough fight in key states and was tailoring the president’s travel accordingly.
“We are going to Colorado today because we know the race is going to be close, because we know that women and families in Colorado care deeply about having access to affordable healthcare, and that’s why the president is going there to talk about it,” Psaki said. “We are not leaving any stone unturned, we are not taking any votes for granted.”
In an advertising blitz focused on a dozen pivotal states, Obama and his fellow Democrats have hammered Romney’s record as a private equity executive at Bain Capital, accusing him of plundering companies and shipping jobs overseas.
The Obama team has created more than 20 new ads since June, many of them seeking to contrast the president’s policy stances and those expected from Romney.
Romney has centered his campaign on the notion that he would be better than Obama at dealing with the economy - the dominant issue for 2012 voters, according to the Reuters/Ipsos poll. His campaign spent $30.8 million on broadcast, cable and radio ads in July, compared to $50.3 million by the Obama camp, according to SMG Delta, which tracks political ad spending.
Restore Our Future, the pro-Romney outside fundraising group or “Super PAC,” was absent from the airwaves for much of the summer, but is back on television screens in 11 states with a $7.2 million ad buy highlighting the former governor’s success at turning around the Salt Lake City Olympics’ budget deficit.
The pro-Obama Super PAC Priorities USA has been running attack ads since early May and is planning to invest $20 million in this latest blitz. The group has run six ads painting Romney as a cruel corporate raider, five of which feature workers laid off by companies bought out by Bain Capital.
“Super” political action committees can raise and spend unlimited funds but cannot coordinate with official campaigns.
Last week, Ken Goldstein of the ad buy-tracking firm Kantar Media said that of the $246.2 million spent on campaign ads in this election cycle, only 28 percent went toward positive hits, while 72 percent paid for negative ones. Most have focused on nine states: Colorado, Iowa, Nevada, New Hampshire, North Carolina, Ohio, Pennsylvania, Virginia and Florida.
Both candidates will also focus their campaigning on swing states next week. Romney is taking a bus tour in Virginia, North Carolina, Florida and Ohio starting on Saturday, and Obama will travel to Iowa for a three-day bus tour starting on Monday.