Clinton Leads Trump in Pennsylvania, Dead Heat in Other Battleground States

— -- A poll tracking the race between Hillary Clinton and Donald Trump in several key battleground states shows Clinton leading Trump in Pennsylvania, but within the margin of error in Iowa and Ohio.

According to the poll released today by NBC/WSJ/Marist, Clinton has emerged with a statistically significant 9-point lead over Trump in Pennsylvania.

Some 48 percent of registered voters said that they would vote for Clinton in the general election and 37 percent said that they would vote for Trump. This represents a gain for Clinton, who polled at 45 percent according to a July NBC/WSJ/Marist poll in the state, leading Trump who polled at 36 percent.

Both candidates have made several appeals to Pennsylvanian voters. At a campaign stop in North Dakota on May 26, Trump said, “I think I’m going to win Pennsylvania easily. We have tremendous support there.”

Voters in Pennsylvania have voted for a Democratic presidential candidate in the past six presidential election cycles. In 2012, 52 percent of voters in Pennsylvania voted for Barack Obama.

In Iowa and Ohio, Trump and Clinton are neck-and-neck. According to the NBC/WSJ/Marist poll, Clinton polled at 41 percent and Trump polled at 37 percent, within a margin of error of 3.3 percent in Iowa. In Ohio, Clinton polled at 43 percent and Trump polled at 38 percent, within a margin of error of 3.3 percent.

In a July NBC/WSJ/Marist poll, Clinton and Trump were tied in Ohio at 39 percent and were in a statistical dead heat in Iowa, where Clinton polled at 42 percent and Trump polled at 39 percent, within the margin of error of 3.4 percent.

Pennsylvania, Iowa and Ohio are all considered important battleground states. Like voters in Pennsylvania, voters in Iowa and Ohio went for Barack Obama in 2012 and in 2008.

ABC News’ Ryan Struyk contributed to this report.