Donald Trump has pulled level with Hillary Clinton in Pennsylvania, at 46 percent each, according to a new poll by Harper Polling.

The poll shows “signs of the race trending Trump in the waning days of the campaign, Donald Trump and Hillary Clinton are tied in the Keystone state (46-46%, 2% Johnson, 1% Stein, 4% Undecided),” said a statement by Harper Polling, which earns a good score in Nate Silver’s ranking of polling firms.

Trump’s gain in Pennsylvania could be decisive, because he needs to win one of the traditionally Democratic states to reach the victory line at 270 Electoral Votes, assuming he wins all the other states where he has a polling lead.

The Pennsylvania poll surveyed 504 likely voters and has an error margin of 4.4 percent. That margin means that 19 out of 20 of the poll results are within 4.4 percent of the true number. The poll was taken Nov. 2 to Nov. 3, using an automated phone call.

In 2012, President Barack Obama won the state by 5.2 percent, earning 20 Electoral Votes. In 2008, Obama won the state by 10.3 percentage points.

The average of recent poll results displayed by the RealClearPolitics website shows Clinton ahead by 3 percent, down from a several-point lead for most of October.

The numbers within the Harper poll reflect broad national trends:

Clinton has a steady lead with women (49% Clinton-44% Trump) while Trump has expanded his advantage with men (43-49% …. Independents prefer Trump (26-46%) but self-identified Moderates choose Clinton (57-31%).

Trump’s gains are built on a 9-point jump since September in the state’s heavily populated southwest, around Pittsburgh, and in the northern part of the state. Clinton has not been able to expand her strong 32-point advantage in the main population center around Philadelphia.