WASHINGTON — The Federal Communications Commission is expected to repeal net neutrality rules Thursday, a move that will likely have major implications for internet service providers, startups and consumers.

The hotly contested move centers on a set of regulations passed in 2015 by a Democratic-controlled FCC that prohibited broadband companies from blocking websites, slowing connection speeds and charging for faster delivery of content.

To enforce the rules, the FCC classified broadband as a more highly regulated utility-like service under Title 2 of federal telecommunications law.

But in January, President Trump appointed Ajit Pai, a Republican and outspoken advocate for the repeal of net neutrality’s regulations, as FCC chairman. He’s argued that the “overhang of heavy-handed regulation” imposed by the FCC hurt the broadband industry and prevented investment in expanded networks.

Thursday’s vote is expected to fall along party lines, and the FCC is now controlled by a Republican majority.

A major point of concern for net neutrality advocates is the idea of paid prioritization – the concept that a telecommunications company could charge an additional fee to transport certain forms of content at a higher speed through its network.

Broadband companies and other internet service providers say they have no plans to offer paid prioritization, but some have been laying the groundwork for it in recent months.

If net neutrality regulations are repealed, content providers such as Netflix or Google could end up paying more to ensure customers get the same service speed. In fact, both of these companies have lined up in favor of net neutrality – over the summer, Netflix posted a banner on its homepage showing its support, while Google elaborated on its views in a post on its public policy blog.

But some of those same large content providers also have the money and the leverage of thousands of subscribers to negotiate deals with internet service providers, get in the so-called fast lanes for service speed and possibly give themselves a leg up on the competition.