The poll marks the first time voter approval of Christie has dipped below 50 percent since 2011, according to Politicker NJ.
While overall approval of the governor is down, 77 percent of Republicans in the state still approve of Christie. However, 89 percent of Republicans approved of the job Christie was doing in January.
Monmouth University Polling Institute Director Patrick Murray attributed Christie's fall to the bridge scandal and how it has overshadowed his accomplishments.
"This hole is getting deeper. Christie’s image as the hero of Sandy is now just a fading memory," he said.
The Monmouth University/Asbury Park Press poll surveyed 803 New Jersey residents via phone Feb. 19-23 with a margin of error plus or minus 3.5 percentage points.