Thousands gathered in Old City Monday for a massive election eve rally at Independence Mall in Philadelphia with the Obamas in attendance and performances by Bon Jovi and Bruce Springsteen.

Clinton supporters lined up hours in advance for the rally, which was open for free to the public. The lines stretched more than a mile down to Washington Avenue in South Philly.

"Tomorrow, the world is watching," Jon Bon Jovi told the crowd, to cheers, before belting out an acoustic rendition of "Living on a Prayer."

"I want to thank you if you’ve been with Mrs. Clinton throughout this campaign. ... Take pictures because you’ve got a front row seat to history," he told attendees. "I’ve known Mrs. Clinton for more than 20 years now. I know she’s been through a lot to get to this place and this time, and I’m very proud to be here on her behalf."

Hard Hats for Hillary, a group of pro-Clinton union laborers, rallied outside the event in support of Clinton's "plan for the biggest infrastructure program since World War II."

The group has "supported Hillary since early in the primary process and why they’ll be there right up to the final minute of this election, including at this get-out-the-vote rally in Philadelphia,” spokesman Brent Booker said.

It's the culmination of months of electioneering, as Philadelphia prepares to go to the polls to help pick the country’s next commander-in-chief.

Last weekend alone, volunteers for Clinton knocked on more than 1.3 million doors in 286 neighborhoods to help get out the vote, campaign officials said. 

A Democratic stronghold, Philly has been targeted by Donald Trump and his campaign surrogates in recent months with claims of rampant voter fraud. City leaders promptly returned fire, denying that there is any evidence of widespread voter fraud.

As Congressman Bob Brady told Metro, “There’s no indication we ever stole an election. We don’t have to, we got enough voters to win.”

Adding to the chaos, a report surfaced that a white supremacist group planned to disrupt the vote in black communities by handing out “40s and weed.”

The plan was eventually revealed to be a hoax, but all the tumult led the Department of Justice to announce plans to monitor polls in Philadelphia, in part after calls from Sen. Bob Casey, D-Pa. 

“The bedrock of our democracy is the right to vote, and the Department of Justice works tirelessly to uphold that right not only on Election Day, but every day,” U.S. Attorney General Loretta E. Lynch said in a letter issued Monday.

The justice department's civil rights division will be monitoring the polls in Philadelphia, as well as in Allegheny and Lehigh counties, Lynch said. Voters with issues can contact the DOJ at 1-800-253-3931 or 202-307-2767.

Locally, the Philadelphia District Attorney’s Office will have 70 prosecutors and “several dozen detectives” on an Election Fraud Task Force, which will be ready to respond to any concerned voters. The task force can be reached at 215-686-9641/9643/9644.