An activist-sponsored billboard slamming Sen. Kyrsten Sinema appeared Wednesday off Interstate 17 in Phoenix.

The digital billboard, on the south side of the freeway at Seventh Street, was crowd-funded in March by net-neutrality activist group Fight for the Future.

Its message: "Sinema is corrupt. She's siding with corporate donors to kill net neutrality so you pay more for worse Internet."

The crowdfunding campaign started after Sinema, D-Ariz., became one of the few Democrats in Congress who didn't sign on to the Save the Internet Act, a net-neutrality bill intended to reverse the Federal Communication Commission's 2017 decision to allow providers to customize internet-access services.

Instead, she joined an otherwise-Republican working group to draft legislation that would encourage internet providers to treat traffic to all websites equally. She said she didn't think the Democratic bill would pass the Republican-controlled Senate, so she and her Republican colleagues were trying to shape a bipartisan solution that can.

“Net neutrality is critical to maintaining a vibrant internet,” Sinema said in a statement at the time. “We need a modern, internet-specific framework that encourages the freedom and innovation that make the internet the vital tool it is today — and consumers and providers need stability.”

But Evan Greer, deputy director of Fight for the Future, accused Sinema of only caring about the interests of telecom lobbyists, saying it is the only way to explain her opposition to a bill all other Democrats support.

“The only way to explain this is corruption, pure and simple," Greer said in a statement Wednesday. "Sinema has decided she’d rather throw her constituents’ Internet freedom under the bus than anger her Big Cable donors."

Sinema's office declined to comment on the group's criticisms in March and again Wednesday, saying her work on the issue speaks for itself.

Reach the reporter at alexis.egeland@azcentral.com or 602-444-8167. Follow her on Twitter @alexis_egeland.

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