Hillary Clinton, with a commanding lead in recent Pennsylvania presidential polling, continues to stump in the state as if she were running neck-and-neck with Donald Trump.

The Democratic presidential nominee went to West Philadelphia High School on Tuesday for a voter registration rally, one day after Vice President Biden took the stage with the former secretary of state in Scranton.

Clinton knocked her Republican opponent as campaigning with "such negativity," and cast herself as a hopeful candidate seeking to register three million people to vote.

The crowd's longest, loudest cheer came when Clinton vowed to "take on the gun lobby." Clinton said she did not oppose Second Amendment rights but called for "comprehensive background checks."

"What that means is, I want to keep you from getting shot by someone who shouldn't have a gun," she said.

Clinton also contrasted her economic policies with Trump's, pitching him as a candidate looking to help the wealthy at the expense of everyone else.

She pledged to fund early education efforts, make college more affordable, and help students repay education loans.

"I'll tell you how we're going to pay for it," Clinton said. "We're going after the super wealthy. We're going after the corporations. We're going after Wall Street to make sure they pay their fair share."

Clinton had some help stirring up the crowd from Mayor Kenney, who told a packed gymnasium, "We have to stop this madman." Kenney did not say whom he was speaking about. The crowd made clear it knew.

Four polls in the last two weeks - NBC-Wall Street Journal-Marist, Quinnipiac University, Susquehanna Polling & Research, and Franklin and Marshall College - show Clinton's lead over Trump expanding to 10 or 11 percentage points since the end of the Republican and Democratic National Conventions in July.

Priorities USA, a Super PAC supporting Clinton, on Tuesday confirmed that it would put on hold television campaign commercials in Pennsylvania from Sept. 3 to 19. The group already put holds on ads in Virginia and plans to hold ads in Colorado during the same period as Pennsylvania.

An average of polls in those two states, prepared by RealClearPolitics.com, shows Clinton with double-digit leads there as well.

Trump is a long way from his victory in the Pennsylvania Republican primary election 16 weeks ago, when he took 56.6 percent of the votes while easily defeating U.S. Sen. Ted Cruz of Texas and Ohio Gov. John Kasich.

During a campaign stop in Altoona on Friday, Trump predicted "the only way" Clinton's campaign can win Pennsylvania "is if in certain sections of the state, they cheat."

The Republican nominee exhorted his supporters to "go around and . . . watch other polling places" on Election Day.

Trump's campaign on Tuesday linked Clinton's visit to the conviction Monday on perjury charges of state Attorney General Kathleen G. Kane.

Kane, who announced Tuesday that she is resigning, was a volunteer coordinator on Clinton's 2008 presidential campaign in Pennsylvania. Former President Bill Clinton campaigned in 2012 for Kane.

"Hillary Clinton's visit to Philadelphia was timed perfectly with Kathleen Kane's conviction on perjury," said David Urban, a senior adviser to Trump in Pennsylvania. "Pennsylvania voters have only one question for Hillary today: Does she think it's OK to lie under oath?"