Poll: Clinton, Trump in tight race in Pennsylvania
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Hillary ClintonHillary Diane Rodham ClintonSessions says FBI agent Peter Strzok no longer has his security clearance Melania Trump puzzles with 'I really don't care' jacket Grassley wants to subpoena Comey, Lynch after critical IG report MORE and Donald TrumpDonald John TrumpCNN analyst Kirsten Powers: Melania's jacket should read 'Let them eat cake' CNN's Cuomo confronts Lewandowski over 'womp womp' remark Sessions says FBI agent Peter Strzok no longer has his security clearance MORE are in a tight race in Pennsylvania, according to a new Public Policy Polling survey.

Clinton leads Trump in a matchup by just 1 point, 41 to 40 percent. Libertarian presidential nominee Gary JohnsonGary Earl JohnsonWithout ranked voting, Pennsylvania's slim margins hide voters' preferences If weed is no longer a crime, why are people still behind bars? Gary Johnson: Trump admin marijuana policy shift could cost him reelection MORE garners 6 percent support in the poll, and Green Party candidate Jill Stein gets 3 percent.

In a head-to-head matchup between both presumptive presidential nominees, Clinton and Trump tie at 44 percent.

But Republicans are more unified around Trump than Democrats are around Clinton, according to the poll, which was conducted before Clinton clinched the nomination. 

Democratic presidential candidate Bernie SandersBernard (Bernie) SandersBernie Sanders: Trump thinks like an authoritarian Democrats protest Trump's immigration policy from Senate floor Trump's America fights back MORE holds a larger lead over the presumptive GOP nominee in a matchup. Sanders has 45 percent of the vote, compared to Trump's 36 percent. Johnson has 5 percent support in the matchup, and Stein takes 1 percent. 

In a head-to-head matchup between Trump and Sanders, Sanders leads Trump 51 to 39 percent.

Among those who support Sanders in a head-to-head matchup with Trump, 72 percent say they would support Clinton and 10 percent say they would support Trump. The remainder of Sanders supporters say they would support Stein, Johnson or are undecided.

Clinton would hold a more comfortable lead over Trump in the state if she could win over Sanders supporters, according to the poll.

Trump also has a high unfavorable rating in the state. Only 34 percent of voters view him favorably and 59 percent have a negative opinion of the candidate. 

The survey was conducted among 1,106 registered voters from June 3 to 5. The margin of error is 3 percentage points.

The survey was conducted before Hillary Clinton became the Democratic party's presumptive nominee. Now, Clinton is looking to garner the backing of Sanders supporters as she pivots to the general election. But the Vermont senator has vowed to stay in the race and fight for every vote and delegate.