Tim Canova, in a blue shirt, joins Verizon protesters on May 25 in Pembroke Pines, Fla. The little-known law professor is challenging Rep. Debbie Wasserman Schultz (D-Fla.) in August's primary (Angel Valentin/For The Washington Post)

Tim Canova was driving from a rally against money in politics to a protest against chemical giant Monsanto this month when his spokeswoman called to tell him that Sen. Bernie Sanders had just gone on CNN and endorsed his long-shot primary challenge against the chairwoman of the Democratic National Committee.

It was a rather big moment for a little-known law professor with a shaved head who, in another year, might not have created so much as a ripple for Debbie Wasserman Schultz, who is seeking her seventh House term and has won all her previous elections in landslides.

A few hours later, Sanders called Canova for the first time — and the next day signed a fundraising email for him. Over the next 48 hours, Canova brought in about $300,000.

Canova, 56, finds himself in the right place at the right time. Wasserman Schultz, 49, has become increasingly unpopular within the liberal base of the party — and among Sanders’s supporters in particular. Though she claims to be neutral in the presidential nominating contest, many Berniecrats believe that she has tipped the scales in Hillary Clinton’s favor. They see her, as they see Clinton, as beholden to wealthy donors and focused on winning elections at the expense of advancing progressive principles.

Since that’s what Canova’s campaign is all about, his bid has become a proxy battle for everything dividing Democrats this year.

“She’s emblematic of an establishment not serving the grass roots,” Canova said of his opponent during a two-hour interview as he sipped a shot of espresso in a bohemian coffee shop here, not far from the beach. “In a presidential election, a lot of people vote for Hillary because they don’t want to lose to Trump and they think she’s more electable. This is such a safe Democratic district that there’s less of that calculation. So it’s really pitting a progressive grass-roots campaign against a corporate machine. What’s it going to be? This is a fight for the future of the Democratic Party.”

Just as Sanders’s challenge has brought unwelcome attention to Clinton’s vulnerabilities, so, too, has Canova shined a spotlight on Wasserman Schultz’s weaknesses as the head of the DNC. Even if she beats back this August primary challenge, which she is ultimately favored to do, the ferociousness of the criticism has exposed her unpopularity within the Democratic grass roots. It has also raised the volume on the question of whether she should continue in her party post.

Sanders has focused national attention on the matter by declaring his desire to replace her.

For Sanders’s supporters, the list of Wasserman Schultz’s offenses is long. There was a primary debate schedule, with several weekend events, that seemed designed for as few people to watch as possible. There is the view that she overreacted to a party data breach by the Sanders campaign, after which he was cut off from a crucial voter file just weeks before the Iowa caucuses. The file is the party’s in-house database of information about likely voters, the lifeblood for any serious campaign.

In February, the DNC rolled back restrictions first proposed by candidate Barack Obama in 2008, banning donations from federal lobbyists and political action committees. The final straw came two weeks ago when Wasserman Schultz faulted Sanders for his response to the chaos at the Nevada state convention.

And no one has forgotten that she was Clinton’s national co-chairwoman during her 2008 campaign against Obama. “If Democrats are unified coming out of the convention, it will be in spite of her — not because of her,” Canova said.

Canova is trying to figure out how to scale up a campaign apparatus to compete with one of the most powerful figures in Democratic politics. Obama has endorsed Wasserman Schultz, and Vice President Biden is coming down next month to headline a fundraiser for her.

When Canova walked into his campaign headquarters in a downtown storefront here — adjacent to a Pilates studio he frequents a couple of times a week — a dozen 20-somethings working the phones on his behalf said “Hi, Tim” almost in unison.

“They make you feel like a rock star,” Canova said, mopping the sweat from his shaved head after walking in from the tropical heat. “It’s crazy.”

He noted later that he didn’t even recognize three of the volunteers, which made him feel like “the movement” was growing. The phone bankers rang little bells every time they persuaded a voter to consider voting against the incumbent. They were ringing a lot of bells, and suddenly cable bookers wanted him on their shows.

“In some circles, she’s very popular. But it’s a big district,” Canova said. “I don’t think she’s loved. I think she’s feared.”

Only a small slice of South Florida will vote, but Canova is doing everything he can to nationalize the race.

The Communications Workers of America and National Nurses United, two unions that back Sanders, have endorsed him. On Friday, he secured the support of Democracy for America, an outside group that has been supportive of Sanders.

Wasserman Schultz responded a few hours later by announcing the support of the Congressional Black Caucus PAC.

All told, Canova has now raised nearly $1.5 million. Like Sanders, almost all of it has been small-dollar donations that were collected online. Most of it is from outside the state, but Canova says he won’t travel outside Florida for fundraisers.

“I’ve gotten invites to go to Los Angeles and New York. People are saying I should go to the Democratic convention for attention, but I’m staying right here,” he said, noting that he has not left Florida since December.

After joining a union-sponsored protest outside a Verizon store in Pembroke Pines on Wednesday night, Canova went home to speak via Skype with a group of progressive activists on Long Island. They then made calls on his behalf into the district, canvassing registered Democrats.

“The eyes of the country are on this district,” he told 40 activists at the Verizon picket line. “We’re getting support from all over the country, but that doesn’t mean anything if we don’t convert it to votes.”

Even Wasserman Schultz’s allies acknowledge that the influx of cash has given Canova credibility. But this is not the most fertile territory to sow the political revolution Sanders and Canova seek. Clinton won the March presidential primary in the 23rd District with 68 percent of the vote, compared with 31 percent for Sanders.

The district is largely made up of the very voters Sanders has failed to make inroads with during the long nominating contest. It stretches along the coast and then covers lower-income inland areas: 38 percent of the district’s voters are Latino, and 10 percent are African American.

Canova, who teaches at Nova Southeastern University in Fort Lauderdale, decided to launch his bid back in January primarily because of Wasserman Schultz’s support for giving Obama fast-track authority to negotiate trade deals.

He opposes “open borders,” though he supports some pathway to citizenship. But the insurgent said he believes that Hispanics will support him once they hear that Wasserman Schultz took money from people tied to the payday loan industry and that African Americans will back him because he opposes the war on drugs. (Wasserman Schultz opposed a ballot referendum to legalize medical marijuana.)

Much of Canova’s campaign literature emphasizes his opposition to the nuclear agreement with Iran, a position shared by many in the district’s large and active Jewish population. Wasserman Schultz backed the deal.

“She’s Jewish; I’m not. But I’ve had a Jewish stepdad for 40 years, and I was a volunteer on a kibbutz. . . . And she voted for the Iran agreement,” he said. “Either she got duped by [Obama deputy national security adviser] Ben Rhodes or she was in on it.”

Canova draws heavy inspiration from Rep. Dave Brat (R-Va.), who, like him, was a college professor at a relatively obscure school when he toppled House Majority Leader Eric Cantor in 2014. He’s also closely studying how Paul Wellstone (D-Minn.) got elected to the Senate in 1990 when he was a professor at Carleton College.

“A lot of consultants tell you to spend money on consultants; that’s not how these guys got elected,” he said. “I’d like to think I’m following that blueprint.”

Canova has held off hiring an admaker. Instead, he’s using the Sanders windfall to open four new field offices. He also had resisted hiring a pollster but changed his mind with all the donations pouring in. “We just got someone,” he said. “We’re going to start polling now.”

Wasserman Schultz is determined not to get caught flat-footed. Even detractors say she comes home fairly often. “Cantor wasn’t paying attention; that’s not an issue here,” said Mitch Ceasar, a national committeeman who was the longtime chairman of the Broward County party. “This is not going to be an easy race, but Debbie is a very hard worker, and I’m sure she takes the challenge seriously.”

Wasserman Schultz’s campaign declined to make her available for an interview, but a spokesman sent the names of four local Democrats willing to speak about her — and made the point that Canova is a newcomer to Florida who doesn’t understand how deep her roots are in the area.

The mayor of Hollywood, Peter Bober, whose law office is two blocks from Canova’s campaign headquarters, praised the congresswoman for being accessible and helping the city get reimbursement from the Federal Emergency Management Agency.

“I really don’t know who this gentleman is,” Bober said of Canova. “I cannot recall seeing him at city hall or a neighborhood meeting or any type of civic event. . . . People recognize Debbie is influential, and that benefits the district.”

Indeed, volunteers at the would-be giant slayer’s phone bank find themselves spelling out his name (“C-A-N-O-V-A”) and hearing people on the other end of the line say they’ve never heard of him.

Canova acknowledges not having deep roots in the community and speaks openly about his transient career path. After working as an aide to then-Sen. Paul Tsongas (D-Mass.), he practiced law at a firm in New York City. Then he decided that he wanted to teach. He bounced around for years in search of tenure, living in New Mexico and California before landing in Florida a few years ago.

Almost six months after announcing, Canova already has lots of war stories about what it is like to run against the head of a national political party. He had to threaten a lawsuit, he said, before the Democrats gave him access to the voter file.

He put $15,000 that he had been saving to buy a house into the campaign as seed money. He waited until April to start building out his staff.

He declined to reveal how many field staffers he has on his payroll. “She should be the last one to realize the extent of what we’re doing,” he said.

Canova has twice approached his rival at campaign events. At one, he tried to hand Wasserman Schultz a letter requesting that she debate him. In his telling, she would not take it.

The two of them showed up at a party brunch last weekend in Weston, near Wasserman Schultz’s home. “There were people who I normally see at these Democratic functions,” Canova said. “When Debbie’s not there, they’ve been warm to me and spoken to me. With Debbie there, they’re afraid to even turn and shake my hand. They certainly don’t want to take a photo with me.”

For now, he’s giving his all to the campaign. He’s a single guy who lives alone and eats lots of Clif Bars.

He has already taken an unpaid leave of absence from law school for this fall.

“If I don’t win, I’ll need the break,” he said. “But I haven’t really entertained the thought of losing. That’s not being cocky. It’s that you don’t want to do this if you dwell on losing. You’ve got to have a positive attitude.”