Poll: Biden leads Trump by 4 percentage points in general election match up

Former Vice President Joe BidenJoe BidenDemocratic convention lineup to include Ocasio-Cortez, Clinton, Warren: reports Whitmer met with Biden days before VP announcement: report Maxine Waters says Biden 'can't go home without a Black woman being VP' MORE leads President TrumpDonald John TrumpJoe Arpaio loses bid for his old position as sheriff Trump brushes off view that Russia denigrating Biden: 'Nobody's been tougher on Russia than I have' Trump tees up executive orders on economy but won't sign yet MORE by 4 percentage points nationwide in a new Hill-HarrisX general election poll. 

Forty-three percent of registered voters said they would support Biden for president if the election were held today. 

By contrast, 39 percent of voters in the July 3-4 survey said the same of Trump.

Five percent of voters said they prefer someone else. An additional 5 percent of voters said they do not plan to vote in the election, one percentage point up from the same survey conducted last month.  

Eight percent of voters are still undecided, down a percentage point from last month. 

The poll found Biden's lead has narrowed from last month's bump, where Trump was trailing the former Vice President by 10 points.

"I think a four point lead should be very concerning," Democratic pollster and founding partner at Hit Strategies, Terrance Woodbury, told Hill.TV.

"We know the enthusiasm gaps between Biden and Trump, with Trump's supporters being very enthusiastic and insistent on voting for him, margins that close are problematic," Woodbury added.

A recent USA Today-Suffolk poll found half of Trump supporters said they were "very excited" to vote for the President while 27 percent of Biden supporters said the same. 

New York Times-Siena College survey from early June showed similar gaps in voter enthusiasm when looking at battleground states.

The latest real clear politics average has Biden ahead nationally by 8.7 percentage points.

 The Hill-HarrisX poll was conducted online among 933 registered voters between July 3 and 4. It has a margin of error of plus or minus 3.2 percentage points. 

Gabriela Schulte