One takes a pint-size dog named Toby almost everywhere, smokes electronic cigarettes and wears his silver hair in a flowing pompadour.

The other has a portrait of Richard M. Nixon tattooed on his back, boasts that he owns more shoes than Imelda Marcos and traffics in conspiracy theories about the Kennedy assassination.

The 2016 election, filled with ugly insults, whispered innuendo and sordid character attacks, features two central antagonists known for their colorful traits and devotion to the dark arts of politics: David Brock and Roger J. Stone Jr.

Each has a passion for his side — Brock for Hillary Clinton and Stone for Donald Trump — and a zeal for attacking critics of his candidate. Their intensity and pugnacity make them either perfect villains or misunderstood masterminds, depending on your point of view.

On the wall of Stone’s office in South Florida, which has an undisclosed address because of the death threats he said he had received, hangs a “Spy vs. Spy” cartoon, which young staff members titled “Brock-Stone” after the two battling operatives.

“The dynamic between the two of them is very interesting,” said Hank Sheinkopf, a Democratic strategist who knows both men. “This will be a battle about who’s tougher.”

Politics has always attracted flamboyant characters with a sometimes-reckless devotion to a cause, and both these men seem to enjoy their outsize images.

Brock, 53, divides his time between Washington and the West Village in Manhattan, throwing lively salons and wooing liberal donors on both coasts, often accompanied by Toby, his schnoodle — a schnauzer-poodle mix.

Stone, 64, has a fashion blog and likes to quote Gore Vidal’s advice to “never miss a chance to have sex or appear on television.” He divides his time between Fort Lauderdale, Fla., and an apartment on the Upper East Side of Manhattan crammed with political memorabilia and Le Corbusier furniture.

“Socially, he’s a very charming, likable, intelligent guy,” Stone said of his rival in a telephone interview Saturday. He praised Brock’s style, saying he is “a dapper guy” and likening his hairstyle to that of the title character in “Eraserhead,” David Lynch’s 1977 surrealist horror film.

But in recent weeks, as sexual assault allegations against former President Bill Clinton surfaced in the campaign, the intersections of Brock’s past with Stone’s attacks on the Clintons have made for a deeper kind of intrigue.

Last week, when Trump brought up a decades-old rape allegation against Clinton in a Fox News interview, Hillary Clinton’s allies saw the influence of Stone. His thinly sourced 2015 book, “The Clintons’ War on Women,” which he wrote with Robert Morrow, focuses on Bill Clinton’s sexual misconduct and accuses Hillary Clinton of silencing women who came forward to complain about it.

But it is reporting by Brock that Stone has used to help Trump make that case.

Before Brock became the man at the center of a multimillion dollar operation built to defend the Clintons, he was a self-described conservative hit man intent on taking them down. He and Stone knew each other socially and would occasionally compare notes.

Reporting for The American Spectator, a conservative newsmagazine, Brock asserted in 1994 that Arkansas state troopers facilitated sexual liaisons for Bill Clinton when he was the state’s governor, allegations that have been central to Stone’s attacks.

“Today, Brock claims his American Spectator stories exposing Bill Clinton were false,” Stone wrote in his book. “He’s lying.”

Brock declined to be interviewed about Stone.

Brock now runs Correct the Record, a super PAC that coordinates with the Clinton campaign to defend Hillary Clinton, and American Bridge, a related group that digs up opposition research to defeat Trump. (Enough to “knock Trump Tower down to the subbasement,” as Brock put it in remarks to liberal donors, according to Politico.)

His mission now will largely be to get inside Stone’s complicated head to anticipate, and stay ahead of, Trump’s attacks. Hillary Clinton’s allies have vehemently denied that she was involved in silencing Bill Clinton’s accusers, but Trump will continue to push that assertion as the two candidates battle for the support of women voters.

Stone acknowledged that Brock’s operation has significantly more resources, but he said the traditional tactic of dismissing these accusations as sordid rumors could backfire. “Brock is calling us conspiracy theorists and trying to make us all sound kooky,” he said. “The only people that scares away are the elites.”

Brock’s group Media Matters for America has taken direct aim at Stone, labeling him “the underbelly of the Trump machine” and assemblingan encyclopedia on his tactics, including his involvement in a National Enquirer article that accused Sen. Ted Cruz’s father of associating with Lee Harvey Oswald before President John F. Kennedy’s assassination. Stone calls Media Matters part of “the Clinton slime machine.”

Both men operate outside the official campaigns, though Brock directly coordinates with the Clinton campaign through Correct the Record. Stone said he had “no formal or informal role” within the Trump campaign, but he is close to Trump and has had a major influence on strategy.

And both have taken risky moves that have created drama and tensions within the campaigns they are ostensibly helping.

Stone hit a rough patch with Trump after the first Republican primary debate in August, when he advised Trump to stop attacking Megyn Kelly of Fox News. Trump said he fired his longtime friend and adviser. Stone said he quit.

Since then, a detente has occurred.

Hillary Clinton has embraced Brock ever since his flattering 1996 biography of the first lady, “The Seduction of Hillary Rodham,” and, later, his 2002 book, “Blinded by the Right: The Conscience of an Ex-Conservative,” which Clinton said provided evidence of a “vast right-wing conspiracy” against her and her husband.

The Clintons encouraged Brock to start Media Matters, and Bill Clinton used to hand out copies of “Blinded by the Right” that he kept in the couple’s Chappaqua, N.Y., home.

As the campaign intensifies, Brock and Stone are likely to keep clashing.

When CNN barred Stone from the network in February, after he had used racial and gendered slurs in describing two of the network’s commentators, he accused Brock of influencing the cable channel. “As Media Matters continues its campaign to highlight the worst of Roger Stone’s history, we encourage other networks to follow suit,” Bradley Beychok, the president of Media Matters, said at the time.

Stone said the move was part of Brock’s “suppression game” with mainstream news outlets that he said were increasingly irrelevant in the social-media era. He wrote on Twitter: “My exposing Bill Clinton’s serial rapes and Hillary’s bullying his victims seems to have gotten under @davidbrockdc’s skin.”

Not long after that, Brock’s Correct the Record said it would spend $1 million to defend Hillary Clinton against attacks on social media. Perhaps it will start with Stone’s Twitter feed.