Just days before Sen. Robert Menendez (D-N.J.) is set to take over as chairman of the prestigious Senate Foreign Relations Committee, he finds himself embroiled in a potential scandal involving a campaign contributor and Dominican prostitutes.

The questions also come as Menendez is playing a lead role in helping craft a bipartisan immigration reform plan.

The Daily Caller first broke the story of a possible inquiry last week, but the Miami Herald reported Wednesday that federal agents actually raided the home of Dr. Salomon Melgen, who is "suspected of providing free trips and even underage Dominican prostitutes" to Menendez. Melgan is also a frequent campaign contributor to the New Jersey lawmaker.

The senator's spokesman vigorously denied the story, saying, "Any allegations of engaging with prostitutes are manufactured by a politically-motivated right-wing blog and are false."

Whether the investigation will ultimately hurt the senator's political standing is still unknown. Menendez isn't up for re-election until 2018 and a colleague, Sen. David Vitter (R-La.), faced prostitution allegations several years ago but was easily re-elected.

But the new allegations come just weeks after Menendez's office was also accused of intervening with federal immigration agents who wanted to arrest and deport an illegal immigrant — who was also a registered sex offender — working in the senator's office.

The smoke of scandal threatens to choke Menendez's power just as it reaches new heights in the Senate.