New Jersey Sen. Robert Menendez beat corruption charges last year but he’s now locked in a tight race for re-election, according to a poll released Wednesday.

Menendez, a two-term Democrat, leads his GOP challenger, pharmaceutical executive Bob Hugin, by a slim 43 to 37 percent, the Quinnipiac University poll reported.

In March, Menendez was ahead by a comfortable 49 to 32 percent.

Any incumbent who can’t reach 50 percent is considered vulnerable.

Menendez was indicted on federal bribery charges, but the case ended in a hung jury last fall. He was accused of accepting bribes from Dr. Salomon Melgen, a Florida ophthalmologist, in return for political favors.

Menendez maintained his innocence — but the stench of sleaze remains.

“As Sen. Robert Menendez sees his once-dominant lead whittled down to single digits, New Jersey voters are sending a clear message. They are troubled by the ethics cloud hanging over him,” said Quinnipiac polling analyst Mary Snow.

The Garden State has long trended blue in federal races for Senate and the presidency.

Cory Booker, the former mayor of Newark, is the other Jersey senator.