(CNN) - Senate Majority Leader Harry Reid, D-Nevada, has taken a seven-point lead overRepublican opponent Sharron Angle, according to a new poll published Friday in the Las Vegas Review-Journal.
The poll, conducted by Mason-Dixon, shows Reid ahead of Angle, 44 to 37 percent, with a 4 percent margin of error. The poll is the first Mason-Dixon survey showing Reid's lead exceeding the sampling error. Voters will decide the contest in November.
Ten percent of the poll's respondents were undecided, while 9 percent preferred someone other than the two major party candidates.
Reid's aggressive advertising campaign, according to the survey, has eroded Angle's support across the board. Angle's support has dropped 9 percent among men and 5 percent among women. While she still dominates among Republicans, her support has dropped by 11 percent with GOP voters. She's also fallen by 6 percent among independents, and 4 percent among Democrats.
The poll of 625 likely Nevada voters was conducted by phone from July 12-14.