The anti-Romney ad released this week by Priorities USA has been widely skewered as over-the-top and irresponsible, condemned for insinuating that Mitt Romney is to blame for the death of a woman whose husband lost his job and health insurance after Bain Capital bought his steel mill.

Priorities USA is offering no apologies.

The provocative ad from the pro-Obama group — which has yet to actually air as a paid television commercial, according to a political ad tracking company — has drawn as much attention as any single spot so far in the campaign, breaking through a jumble of other messages and sound bites to dominate the political discussion for two days running.

Increasingly, for campaigns on both sides, that is the entire goal: to somehow rise above a cluttered media landscape, no matter how outrageous a message that requires.

That has led to a flood of statements, ranging from creative to incendiary, by the campaigns and their allies in recent days. Senate Majority Leader Harry Reid (D-Nev.) has claimed that Romney did not pay taxes in multiple years. Democrats have produced an ad showing Rep. Allen West (R-Fla.) punching a woman. President Obama accused Romney of being Robin Hood in reverse, calling his positions “Romneyhood,” which his rival countered by saying the president is full of “Obamaloney.” On Thursday, Romney released an ad claiming that Obama is waging a “war on religion.”

The push-the-envelope approach is not entirely new. Two years ago, Republican Senate candidate Carly Fiorina released an eyebrow-raising “demon sheep” ad accusing her rival of being a wolf in sheep’s clothing, complete with video of red-eyed sheep. And in the Democratic primaries in 2008, the ad that drew the most attention was a warning from Hillary Clinton’s campaign that Obama was not ready to face a national security threat at 3 am — a message conveyed in an ominous ad.

But this year’s cascade is notable in part because it is so early — and there seems to be little incentive for either side to tone it down. The trend is so widespread that it has already become the subject of a spoof in the Onion, which published a satirical story about a new Obama ad alleging “Romney murdered JonBenet Ramsey.”

“It’s a knife fight in a telephone booth and there is no conventional referee out there who is going to throw a flag that makes a difference, so there’s no downside,” said Chris LeHane, a Democratic strategist. “These ads drive the larger meta narrative of a campaign, and the stories and coverage of the ads and rhetoric will often have a bigger impact than the original ads or comments.”

On Thursday, Romney pushed back against the Priorities USA ad, charging that Obama and his supporters have given up on the hope and change rhetoric of 2008 in favor of a more scorched earth campaign that skirts the truth.

“You know, in the past, when people pointed out that something was inaccurate, why, campaigns pulled the ad,” Romney on Bill Bennett’s radio show. “They were embarrassed. Today, they just blast ahead. You know, the various fact checkers look at some of these charges in the Obama ads and they say that they’re wrong, and inaccurate, and yet he just keeps on running them.”

Bill Burton, who heads Priorities USA, stood by the ad in an interview, and said his group isn’t arguing that Romney literally had a hand in the woman’s death.

“This is one of several stories that we’ve put into ads to make sure people know about Mitt Romney’s business experience and that it has continued to have an impact,” Burton said of the minute-long spot, which got 300,000 views on “And some of the stories are incredibly sad, but that doesn’t mean they should be off limits.”

Even as Romney complained about the veracity and tone of the pro-Obama ads, his campaign released an ad about Obama’s plans for welfare that independent fact checkers judged to be untrue. His “war on religion” ad argued that the Obama health care bill will threaten the freedom of people of faith. “When religious freedom is threatened, who do you want to stand with?” the narrator asks.

The need to be more and more outrageous comes amid an explosion of advertising on both sides, a phenomenon driven not just by the record amounts of available cash, but also by the ease – and relative inexpensiveness – of advertising on the Internet.

While both campaigns have continued to air traditional television ads, they and their surrogates also have produced spots aimed solely at Web audiences, in some cases posting videos more than once per day on their official YouTube channels.

Though Internet videos were used in the 2008 cycle, the 2012 campaign has ushered in a far more sophisticated integration, experts said. The Obama and Romney campaigns use Web videos to launch attacks, respond to attacks and target specific interest groups, and often those ads, which cost very little to produce, end up on cable television and garnering huge audiences.

In July 2008, the Obama campaign posted 66 videos to its YouTube page, of which five were television ads (four attacking rival John McCain and one positive about Obama’s foreign policy vision). The rest were raw video snippets of Obama campaign rallies, endorsements of him and one video about the Democratic National Covention.

By comparison, in July 2012, Obama’s campaign posted 57 videos, including 11 television ads and another 16 highly produced videos produced solely for the Web that attacked Romney and defended Obama against attacks from the GOP’s presumptive nominee.

Most of these Web videos focused on raising questions about Romney’s tenure at Bain Capital, accusing him of sending jobs offshore, and about Romney’s refusal to release his tax returns. A sampling included titles such as “Mitt Romney: Saying Anything to Get Elected,” “Mitt Romney’s Bain Secret Exposed,” and “Why Would Mitt Romney Invest Millions in the Cayman Islands?”

“There is an increase in ads that try to generate moral outrage and anger, that’s what the steelworker ad is trying to do and those are the ads that are highly mobilizing,” said Nicholas Valentino, a University of Michigan political science professor who studies campaign advertising. “It’s a listen up and a call to arms for both sides to say now is the time to donate, to get off the couch and to start to get active.”

Romney, too, has employed a fierce Web-video strategy, posting a series of videos attacking Obama for using the phrase “you didn’t build that” while talking about business entrepreneurs and “it worked” while referring to his economic agenda. The Obama campaign has argued that the Romney campaign has taken the snippets out of context.

In July, the Republican National Committee threw up a Web ad just hours after Obama said the “private sector is doing fine” during a news conference – a video that has garnered 112,000 views on YouTube.

William Hillsman, an independent political advertising consultant, said both campaigns have calculated that it is more important to inspire their bases than to fight over the smaller set of undecided voters who might prefer a more positive approach.

“It’s a calculated use of negative and ridiculous advertising to try to drive [undecided and independent] people away from voting,” Hillsman said. “The more negative a race gets, the more it suppresses voter turnout. A lot of people believe a pox on both their parties. That’s part of the strategy here. It will be a real grind-it-out, nasty kind of race, the farthest thing from the 2008 campaign of hope and change.”

YouTube’s Rob Saliterman, who handles political ads for Republican campaigns, said campaigns have upped the ante by buying TrueView ads that air the ad content before users can watch other unrelated videos across the site. The campaigns only pay for the ads if viewers watch the whole thing, which happens about 20 percent of the time, said Saliterman, a former press official in the George W. Bush administration. He added that “contrast ads,” which are negative in tone, have a higher rate of views than more positive ads, but that the benefits of advertising online are multiple because viewers can forward the ads to their friends, and the campaigns also include links for viewers to donate money and sign up to volunteer.

Late Thursday, after being on the defensive over the Priorities USA ad for two days, the Obama campaign’s answer was to release an ad that tied Romney to one of the “largest tax avoidance schemes in history.”

The ad, called “Son of Boss,” echoes Reid’s unproven claims about Romney’s tax rates and closes with a question:

“Isn’t it time for Mitt Romney to come clean?”