Only 38 percent of the 625 registered Nevada voters polled had a favorable opinion of Reid in the poll released by Mason-Dixon Polling & Research that was commissioned by the Las Vegas Review-Journal.
Forty-nine percent of respondents had an unfavorable opinion of Reid in the poll with 13 percent remaining neutral.
The results follow an aggressive early advertising campaign by Reid.
"I'd be worried," Bowdoin College political advertising specialist Michael Franz tells the Review-Journal. "I'd stop if I had aired ads for two or three weeks and it wasn't moving the needle."
Sensing an opportunity to oust the leading Senate Democrat, Republicans are facing a crowded primary, with 9 candidates running. The leading names are former state party chairwoman Sue Lowden, and businessman Danny Tarkanian.
The Mason-Dixon poll favors Lowden over Reid at 51 percent to 41 percent, and Tarkanian over Reid at 48 percent to 42 percent. The fear that Reid's fifth Senate term could be his last, prompted Vice President Joe Biden to visit Reno in October for a fundraiser.
"It just shows that Reid has reached a point where people aren't listening to him anymore," Tarkanian consultant Jamie Fisfis told the Review-Journal.
Nevertheless, Democratic strategists hope that a divisive Republican primary would boost Reid's numbers.
"They have to go through the primary, and at some point the gloves will come off," pollster Brad Coker tells the Review-Journal. "If the Republican primary becomes a bloodbath, they might change these numbers down the road."