FBI probing extortion of Christine Quinn over carriage horses

Lobbyist Scott Levenson is ­under investigation by three law-enforcement agencies over a wide range of questionable activities during the last campaign cycle, The Post has learned.

The controversial Advance Group boss is being probed by state Attorney General Eric ­Schneiderman, US Attorney Preet Bharara and the city Department of Investigation over potential misconduct — including his alleged strong-arming during the 2013 mayoral race of former Council Speaker Christine Quinn over support for the horse-carriage industry, sources said.

Sources said Levenson is also under official scrutiny for offering “free” consultations to current Speaker Melissa Mark-Viverito while she campaigned for the council-leader post despite City Charter rules that prohibit the practice.

Levenson’s assistance allegedly included helping Mark-Viverito prepare for debates and facilitating meetings with key officials to ease her path to the powerful post.

Reached Friday, the power player insisted he has done nothing wrong, saying, “I’ve spoken to the campaign finance board and there ya go,” he said of the accusations. “That will all be documented, and I think you will find in each of those cases absolutely no wrongdoing on the part of The Advance Group.”

Levenson and his firm have also drawn fire for helping the city’s teachers union dole out piles of money to influence council races while also working for individual candidates, sources said.

Blogger Louis Flores filed an official complaint with Bharara in January that accused Levenson and his outfit of unethical campaign tactics.

“Conduct and activities of The Advance Group during the last election cycle may have involved the coordinating of independent expenditure Super PACs with official campaigns, and The Advance Group provided unpaid lobbying services to a public official and, as a consequence, The Advance Group will benefit from selling access to the public official to influence official acts,” the complaint alleges.

Levenson has come under intense scrutiny for allegedly threatening to bury Quinn with his political resources if she didn’t reverse her support for the horse-carriage operators.

The Advance Group had been hired by an animal-rights group, NYCLASS, to help them wage their war against the carriages.

Quinn refused to buckle under the pressure and was hit with a massive negative advertising blitz that branded her as an animal hater.