Oct. 3 (Bloomberg) -- Barack Obama lashed out at presidential rival Hillary Clinton, rolling out a new strategy for taking on the frontrunner in the race for the Democratic nomination.

Obama, 46, used a speech at DePaul University in Chicago to contrast his consistent opposition to the Iraq war with Clinton's vote to authorize the invasion in 2002. ``Who got the single most important foreign-policy decision since the end of the Cold War right, and who got it wrong?'' said Obama, a first- term Illinois senator.

The attack on Clinton, a senator from New York, came less than a week after Obama passed up opportunities to confront or criticize her in a New Hampshire debate. Trailing her in support and, as of this week, fund raising, he is alternating between the roles of new-style, above-the-partisan-fray politician and challenger on the attack.

Obama's campaign is ``in a little bit of a bind,'' said Dan Gerstein, a Democratic strategist who worked on Connecticut Senator Joe Lieberman's presidential campaigns. While ``they have to figure out a way they can draw a contrast,'' he said, ``if it looks like it's getting too personal it could backfire.''

Obama's staff insists his campaign is on track. They say they are spotlighting Clinton's greatest potential liability: Unfavorable ratings among independent and Republican voters, which play into Democratic concerns she won't be able to broaden her appeal in a general election.

`Polarizing Figure'

``The fact that Senator Clinton is a polarizing figure in American politics is not even a point of debate,'' said David Axelrod, a senior Obama campaign adviser. ``It's an empirical fact.''

Axelrod said the campaign's ``refined'' message would avoid the pitfalls associated with negative attacks. ``We're going to draw those distinctions, but what we won't do is kind of take out a spray gun and indiscriminately fire,'' he said.

Many national polls show Clinton, 59, with a lead of more than 20 percentage points over Obama. He suffered a further blow this week when Clinton reported raising more money than he did, neutralizing his cash advantage in the first half of the year. In the latest period, Clinton took in $22 million that can be used for the primary elections, compared with $19 million for Obama.

Edwards' Attacks

Until now, the Obama campaign has largely relied on others to attack Clinton's record. Former North Carolina Senator John Edwards, who trails both Clinton and Obama in the polls, has accused her of ties with special interests in several debates.

Clinton had the support of 43 percent of Democratic primary voters nationwide, while 22 percent said they backed Obama and 16 percent favored Edwards, according to a CBS News poll of 706 people conducted Sept. 14-16.

Obama didn't mention Clinton by name in yesterday's speech, which commemorated the fifth anniversary of an antiwar address he gave as an Illinois state senator. Still, his criticism of the ``conventional'' thinking that led lawmakers to give Bush the authority to go to war left little doubt who his comments were aimed at.

``No law can make senators read the intelligence that showed the president was overstating the case for war,'' Obama said. ``No law can give Congress a backbone if it refuses to stand up.''

`Political Points'

Obama also rebutted suggestions by the Clinton camp -- including her husband, former President Bill Clinton -- that he is too young and insufficiently seasoned for the highest office. ``When we have a debate about experience, we can't just debate who has the most experience scoring political points,'' Obama said.

He has also begun to draw distinctions with Clinton on health care, an area where she has gained support in recent weeks after unveiling a new plan for universal coverage.

In Chicago yesterday, he referred to the criticism Clinton received as first lady in the 1990s, when she drafted a health- care plan out of public view. ``We don't need another president who shuts the door on the American people when they make policy,'' he said.

Iowa Lead

Campaign officials say national polls don't give an accurate picture of Obama's appeal in states such as Iowa, which plans to hold the nation's first caucus. A Newsweek survey published last week showed he was backed by 28 percent of likely caucus goers, closely followed by Clinton with 24 percent and Edwards with 22 percent.

``The only state where the race is fully engaged is Iowa,'' Obama campaign manager David Plouffe said in an interview.

Both the Clinton and Obama campaigns, with more than $30 million each in cash going in to the third quarter, are on track to have the money they need to pay for the primary fights after Iowa. If Senator Clinton continues to match or exceed her opponent's fund raising, the Obama campaign will lose the comparative cash advantage it was counting on when the voting starts.

``Obama was banking on winning the fund-raising game in order to jump-start the campaign, to pivot off a slow summer where his polls flat-lined,'' said Christopher Lehane, a Democratic consultant who worked for Vice President Al Gore's 2000 campaign and now supports Clinton.

To contact the reporter on this story: Heidi Przybyla in Washington at hprzybyla@bloomberg.net

Last Updated: October 3, 2007 00:10 EDT