Within minutes of the U.S. Federal Communications Commission vote to roll back Obama-era net neutrality regulations, threats of lawsuits to block the move rolled in.

"Allowing internet service providers to discriminate based on content undermines a free and open Internet," said Washington State Attorney General Bob Ferguson in a statement announcing his intention to file challenges along with colleagues from other states.

Democratic Attorneys General Eric Schneiderman, of New York, and Lisa Madigan, of Illinois, also announced plans to sue, as did Free Press, an activism group that helped organize opposition to the FCC's party-line vote to strike down open internet policies. They are likely to be joined by others in coming weeks. But the lawsuits face long odds of succeeding because courts generally defer to the expertise of federal agencies, said James Speta, a Northwestern University law professor who favored the net neutrality rules.