The poll showed 40 percent of likely voters supporting Trump and 39 percent backing Clinton for the week of Aug. 26 to Sept. 1. Clinton's support has dropped steadily in the weekly tracking poll since Aug. 25, eliminating what had been a eight-point lead for her.
Trump's gains came as Republican support for their party's candidate jumped by six percentage points over the past two weeks, to about 78 percent. That is still below the 85 percent support Republican nominee Mitt Romney enjoyed in the summer of 2012, but the improvement helps explain Trump's rise in the poll.