Pennsylvania presidential polls 2016: Here's where Trump and Clinton stand with voters

If Donald Trump wants to get to 1600 Pennsylvania Avenue, he in all likelihood has to win the state of Pennsylvania first.

That prospect is looking increasingly unlikely as a new poll shows Trump falling behind in this crucial swing state. In a head-to-head matchup, Hillary Clinton leads Trump 51% to 42%, according to a Bloomberg poll released Thursday.

Clinton fares well in a four-way race with the top two third-party candidates as well, leading Trump 48% to 39%. The poll was conducted from Oct. 7-11 among 806 likely voters. The margin of error is 3.5%.

Clinton leads Pennsylvania polling averages

Overall, the RealClearPolitics polling average shows Clinton with a healthy advantage in the Keystone State, with a 49% to 40% lead.

Pennsylvania key to Trump's hopes

Trump has been falling in national polls as more bad news about alleged sexual assaults and lewd comments about women (and even an underage girl) have surfaced in recent days. The Trump campaign is clearly in panic mode. Trump is now "running essentially a four state campaign" in the battleground states of Pennsylvania, Florida, North Carolina and Ohio, a source told NBC News.

Trump was in Wilkes-Barre, Pennsylvania, and Ambridge, Pennsylvania, earlier this week where he tried to appeal to working-class voters. 

Pennsylvania has 20 electoral college votes. The state voted for a Democrat in each of the past four presidential elections, according to Ballotpedia.

FiveThirtyEight gives Clinton an 89.4% chance of winning the state.

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