WASHINGTON (CNN) -- Sucker punches and below-the-belts can be expected as we enter the slugfest season of political attack ads. They're already taking off the gloves for what promises to be nasty 2008 campaigns that use the newfound enormous strength and reach of the Web.
The infamous Willie Horton ad was devastating to the 1988 Michael Dukakis campaign.
"If I'm going to get punched in the stomach, I'm going to take a knife out and get you right back," said John Lapp of the consulting firm McMahon, Squier, Lapp and Associates.
Lapp considers himself one of a new breed of Democratic ad-makers who don't hesitate to hit hard in the ad war.
"I'm going to use every single weapon I have in my quiver."
His Republican counterparts agree.
GOP operative Mark McKinnon said to expect an especially ugly ad season over the next year, even though opinion polls consistently show that voters despise negative campaigning. Watch ad where cartoon characters stick head up rears »
"We know from a lot of history and a lot of observation and a lot of science that it works," McKinnon said. He works for GOP hopeful Sen. John McCain and served as media adviser for President Bush's 2004 campaign.
"If you can go at somebody's strengths and hurt them on their strengths," he said, "then you've really done some damage."
On both sides of the aisle, independent expenditure groups are sharpening their knives and filling their coffers for 2008.
The liberal grassroots group MoveOn.Org says it will spend as much as $45 million -- much of it on negative ads. "Sometimes you have to just lay the issues out in very stark terms and fight the fight," MoveOn's executive director Eli Pariser, 26, said.
And on the right: "We're not wallflowers," said Bradley Blakeman, president and CEO of the conservative group Freedom's Watch. "And we're going to come out swinging when we have to."
The proliferation of negative advertising has made Americans more cynical about politics, according to critics. Watch the infamous Willie Horton and Swift Boat ads »
When voters see extreme partisan bickering and slash-and-burn personal attacks, "they basically say, 'a pox on both your parties,'" warned Bill Hillsman, whose Minneapolis-based North Woods Advertising typically represents liberal and independent candidates.
"Negative advertising works in a very insidious way," he said. "It works by depressing voter turnout," which tends to benefit incumbents at the expense of challengers.
Others say negative advertising -- if it's accurate -- actually benefits voters by helping them understand where candidates differ. "The public needs to know about the good and the bad of both candidates," says Vanderbilt University political scientist John Geer. "And the negative ads provide the downside."
Negative campaigning is as old as the Republic. Thomas Jefferson's opponents predicted in their brochures that if he became president, "murder, robbery, rape and incest will be openly taught and practiced."
In the 1828 presidential campaign, Andrew Jackson's opponents accused him of murder, gambling and treason and said his wife was a prostitute.
"What we do on television today, they did 200 years ago," McKinnon said. "In fact, back then it was even tougher."
Today's negative ads are used to throw the opponent's campaign into disarray and force it to spend money countering the attack. Even denying the accusation can backfire by further publicizing the accusation.
Campaigns routinely try to tempt journalists to cover the attack ads as a news story. "The biggest coup you can get in politics is not having to pay for the ads, but getting the free press to cover it," Lapp said.
Recent history shows what can happen if a candidate ignores the basic rule of campaign combat: When attacked, fight back. Former Massachusetts Gov. Michael Dukakis, the Democratic presidential contender in 1988, underestimated the damage from the infamous Willie Horton ad, which portrayed Dukakis as being soft on crime. Watch Dukakis call the ad "racist," "despicable" »
Sen. John Kerry, the Democratic candidate in 2004, made a similar mistake when a smear campaign by Swift Boat Veterans for Truth challenged his record as a Navy lieutenant patrolling the Mekong Delta in the Vietnam War. Kerry's many service medals include three Purple Hearts for wounds received in combat, but the ad claimed his war record was not what he made it out to be.
The 2008 campaign also provides a new frontier for negative advertising: the Internet. It is open, unregulated, anonymous, and dirt cheap. "This will really be the first presidential cycle where ads are going to be made by 13-year-old kids in their basement," Hillsman said.
A prime example is an attack on Sen. Hillary Clinton that was posted last March on YouTube by someone calling himself Park Ridge-47. Titled "Hillary 1984," the ad was a takeoff on a well-known Apple computer ad that premiered during the 1984 Super Bowl to attack IBM's dominance in the industry.
In the new incarnation, Clinton is portrayed as a Big Brother figure droning political pablum to an audience of zombie supporters. The tag line touts Sen. Barack Obama as an alternative to Clinton.
Obama's campaign denied authorizing the attack. Park Ridge-47 was later revealed to be Phillip de Vellis, an employee of an online communications firm that had worked with the Obama campaign.
"I was actually kind of bored watching the presidential race from the sidelines and I was a real fan and supporter of Barack Obama," de Vellis said. "I wanted to make a statement."
His 74-second statement received millions of hits, garnered extensive media coverage, and changed the rules of engagement.
"We're in a brave new world. We're in the Wild, Wild West right now," Hillsman said.
"I think what's changed is accountability," McKinnon said. "It's like people knew who was doing what when and where, and we don't know that anymore. We don't know who's doing it; we don't know where they're doing it, and we don't know how they're doing it." E-mail to a friend