Democratic presidential nominee Joe Biden suffered an embarrassing blunder on Election Day while addressing a crowd in Pennsylvania.

The former Vice President appeared to confuse his son with his granddaughter on Tuesday, in a gaffe that was blasted on social media by the Trump campaign.

'We Got the Wrong One'

Biden was introducing the daughter of his son, Beau Biden, who died of brain cancer in 2015, to supporters in Philadelphia when he called her by Beau's name and incorrectly stated that his late son was elected to the Senate. Beau was elected Delaware Attorney General in 2006 and 2010 but never ran for the Senate.

"I want to introduce you to my granddaughters. This is my son Beau Biden who a lot of you helped elect to the Senate in Delaware," Biden said before immediately correcting himself to say "this is my granddaughter Natalie, Beau's daughter."

Joe Biden
Joe Biden speaking to supporters in Philadelphia, Pennsylvania on Tuesday. Twitter

Biden, who turns 78 this month, then realized that he had his arm wrapped around his other grandchild, Finnegan, and admitted his mistake before pulling Natalie over.

With campaigning wrapped up and both candidates now waiting for the final election results to be declared, the confusion gave President Donald Trump's campaign one final chance to target Biden on social media, sharing the video clip as evidence of Biden's deteriorating mental health condition, which Trump has repeatedly alluded to in the run-up to the election.

"WATCH: Joe Biden mixes up his granddaughters," the Trump campaign posted on Twitter with an accompanying video of the incident. Watch the clip below:

Netizens Claim Biden is Suffering From 'Alzheimer's'

The video footage is now being widely circulated on social mediaand has racked up comments from users who have had family members suffering from senility to associate Biden's confusion and memory loss as symptoms of "Alzheimer's"

"My grandfather has Alzheimer's and as we watched his mind slip the names of his grandkids were very hard for him to remember," wrote one user. "It's a horrible disease and very sad to watch. And it's worse that Biden's family is putting him through this at this time in his life."

"To slip up as much as Joe is its getting to resemble the Alzheimers my uncle and grandma went through," commented another. "Soon he'll ask multiple times where everything is in the room even if its right in front of him."