The University of Connecticut/Hartford Courant poll gives Murphy 37 percent support over McMahon's 33 percent, though that's a statistically insignificant lead, considering the margin of error is 4.4 percentage points.
Murphy leads among both men and women, but McMahon lags among women by only three percentage points -- a stark difference from her 20-point deficit with female voters on Election Day in 2010. That seems to indicate her early efforts to shore up support among that demographic -- including women-centric business roundtables and meet-and-greets -- may be paying off.
The poll indicates, too, that Murphy could have more work to do shoring up the Democratic base than McMahon has to do with Republicans: while only 17 percent of Republicans are undecided, 27 percent of Democrats haven't picked a candidate yet.
The poll was conducted among 517 voters from Sept. 11-16.
--This piece was corrected to reflect the fact that Rep. Chris Murphy leads among both men and women.