Screenshot by CNET

Net neutrality activists and websites like Etsy, Tumblr, Postmates, Foursquare and Twilio will post "red alerts" starting May 9 to protest the FCC's effort to roll back Obama-era net neutrality protections.

This latest protest, announced Monday, is set to coincide with the next step in an ongoing process in the Senate to use the Congressional Review Act (CRA) to halt the Federal Communications Commission's repeal of the 2015 net neutrality rules. On May 9, senators will present a petition to force a vote on a resolution to undo the FCC's net neutrality rollback.

The CRA gives Congress 60 legislative days in which to roll back the FCC's decision. The countdown for the rollback effort began in February when the FCC published its order in the Federal Register to repeal the rules.

The rules, passed in 2015 under then-President Barack Obama, have become highly politicized and are strongly supported by Democrats in Congress and by many internet companies, such as Google and Facebook.

Supporters say the rules are necessary to ensure the internet remains open and offers equal access to all content. Republican lawmakers and big broadband companies, like AT&T, Comcast and Verizon, oppose the rules, saying they're too restrictive and hurt investment.

All 49 Democrats in the Senate support the effort to roll back the FCC's repeal. One Republican, Susan Collins of Maine, also supports the measure. Supporters say they need one more Republican to support the bill in order to send it to the House of Representatives.

The "go red" campaign is run by BattleForTheNet.com, an effort backed by advocacy groups Demand Progress, Fight for the Future and Free Press Action Fund.

The campaign seeks to promote awareness about the vote and to encourage constituents to flood their representatives with phone calls and emails to support the resolution. The online push will begin on May 9 when the resolution is officially presented to the Senate and will continue until the vote.

"This Senate vote will be the most important moment for net neutrality since the FCC repeal," Evan Greer, deputy director of Fight for the Future, said Monday in a statement. "Every Internet user, every startup, every small business -- the Internet must come together to sound the alarm and save net neutrality."

Net neutrality supporters are fighting an uphill battle. If the measure passes the Senate, it still must pass the House, where an overwhelming majority of Republicans are likely to oppose it. After that it would go to President Donald Trump, who is also expected to veto it. Regardless of what happens in Congress, the fight to save net neutrality isn't over.

Several tech companies, like Vimeo, Mozilla, Kickstarter, Foursquare and Etsy, as well as several state attorneys general, have already filed lawsuits to preserve net neutrality protections.

States are also taking matters into their own hands. More than two dozen states, including California, New York, Connecticut and Maryland, are considering legislation to reinstate net neutrality rules within their borders. Earlier this year, Washington became the first state to sign such legislation into law. Governors in several states, including New Jersey and Montana, have signed executive orders requiring ISPs that do business with the state to adhere to net neutrality principles.

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