WASHINGTON ― When Ajit Pai, President Donald Trump’s pick to chair the Federal Communications Commission, announced his plan to roll back his own agency’s net neutrality rules on Wednesday, he sounded nervous.

“I am confident we will finish the job,” he said, in a somewhat stilted speech at the Newseum in Washington, D.C. “This is a fight we intend to wage, and this is a fight we are going to win.”

If Pai is nervous, he has good reason to be. Net neutrality is extremely popular with both Republicans and Democrats. The activists who support strong rules are loud and well-organized, and the organizations that oppose the rules — cable companies like Comcast and telecom providers like Verizon, HuffPost’s parent company — are not loved. When cable and telecom companies lost the fight against the Obama administration’s strong net neutrality rules in 2015, they lost badly. The fight this time could be even fiercer.

In 2014, then-FCC Chairman Tom Wheeler, a former cable and wireless industry lobbyist, said he was planning to avoid the strong net neutrality protections that activists were hoping for. Activists mobilized, fearing a dystopian future where telecom companies could censor websites or slow traffic for a profit. They launched national campaigns, painted Wheeler as a lobbyist sellout, and descended on his house. Comedian John Oliver famously compared the appointment of Wheeler to a dingo watching a baby. (Dingoes eat babies.)

Then-President Barack Obama publicly came out in support of strong net neutrality rules in November 2014, which conservatives have pointed to as evidence that he unduly influenced Wheeler. But the president simply added to the existing momentum, Wheeler said later. And big-weight tech companies had also joined activists in speaking out in support of an open internet. Wheeler proposed strong rules in February 2015 — rules that required reclassifying internet service providers as a “common carrier” under Title II of the 1934 Communications Act — and the FCC was flooded with public comments supporting the decision. The agency subsequently approved the rules in a 3-2 party-line vote.

Now, Pai wants to roll them back and allow the industry to police itself. The agency could take it a step further and propose eliminating any existing rulings on net neutrality, permitted they have a compelling legal case to do so, senior FCC officials told Recode on Thursday. Pai is expected to go through a lengthy rule-making process that includes a period of public comment. (People can start commenting on the draft released today, an agency spokesman said.)

Gigi Sohn, who previously served as counselor to Wheeler, estimates that the repeal process will take at least seven to 10 months. “We know from when we did the net neutrality rules, the groups will make it painful for every single day,” she said. “There will be emails, phone calls, protests ― it’s going to be a tsunami.”

Having now read @AjitPaiFCC's proposal 2 repeal #netneutrality, I would say it leans heavily towards NO rules at all. Not even transparency. — Gigi Sohn (@gigibsohn) April 27, 2017

Pai should know the backlash is coming: He’s active on Twitter, where he is already getting hammered by activists over his proposal. And as a former commissioner who voted against Wheeler’s rules, he was around for the last fight.

This time, the backlash could be even worse. Wheeler’s FCC issued the current net neutrality rules only after an appeals court said it did not have solid legal footing for earlier rules. But that same appeals court upheld the new, stronger rules last year, soundly rejecting arguments from AT&T and other groups that had sued to overturn them. (A petition to rehear the case is pending before the full U.S. Court of Appeals for the D.C. Circuit, where judges appointed by Democratic presidents hold a solid majority.)

Activists are better-prepared for a fight this time, said David Segal, executive director of Demand Progress, a leading pro-net-neutrality group. “People are better networked than they previously were, and are looking for opportunities to engage,” he told HuffPost. “We plan to make use of the internet to save the internet, as we did last time.”

A number of startups, including Engine Advocacy and Y Combinator, have already started circulating a letter opposing Pai’s actions. Public interest groups also created a crowdfunding effort to relaunch BattleForTheNet.com, an activism campaign to help protect the rules.

For now, some of the larger corporations that have supported net neutrality are keeping quiet. Google declined to comment, but directed a reporter to the Internet Association’s statement arguing against any rule change. (Google largely sat out the net neutrality fight in 2014, speaking through think tanks and industry groups then, too.)

Netflix, which became the poster child for net neutrality in 2014, also seems to have tempered its stance. Two days before Trump’s inauguration, the company told investors that weaker net neutrality laws would be unlikely to “materially affect” its U.S. profit margins, though Netflix still supports net neutrality. (Netflix did not respond to a request for comment.)

Pai will likely want support from Congress. But at a time when Republican members of Congress are dogged by angry protesters at nearly every town hall they host, that won’t be an easy ask.

“Congress is a very difficult playing field for him because members of Congress have been so overwhelmed by constituents contacting them in support of net neutrality,” Segal said.

Members of Congress in swing districts, already fearing an anti-Trump wave in 2018, may also shy away from what will likely be a bitter fight. And without an overwhelming majority that includes some Democrats, the specter of a filibuster looms over any net neutrality legislation.

Pai also has to be reconfirmed by the Senate by the end of 2017, and that may occur before his net neutrality fight is over. Though he has support from a GOP-controlled Congress, the outcome of the current battle could influence his reconfirmation chances.

“This is a litmus test,” Sohn said. “And he knows it.”