Biden vs. Trump: Live Updates for the 2020 Election

As the election winds to a close, President Trump and Joseph R. Biden Jr. are converging on Pennsylvania, with both candidates holding a flurry of events in a last-minute quest for votes.

Mr. Trump held four rallies in Pennsylvania on Saturday — in Newtown, Reading, Butler and Montoursville. And on Monday, in what is a clear attempt to needle Mr. Biden, he will head to Scranton, Mr. Biden’s hometown.

Mr. Biden, for his part, is heading to Philadelphia on Sunday, for a “Souls to the Polls” event in the afternoon and a drive-in rally in the evening. His campaign will then barnstorm the state on Monday, with appearances by Mr. Biden; his wife, Dr. Jill Biden; his running mate, Senator Kamala Harris of California; and her husband, Doug Emhoff. Former President Barack Obama recently campaigned on Mr. Biden’s behalf in the state as well.

Recent surveys of Pennsylvania indicate the race there is close: An average of polls shows Mr. Biden with a six-point lead.

But beyond its electoral significance, the state carries great symbolic meaning for both parties. For Republicans, it was one of several longtime Democratic bastions that Mr. Trump flipped four years ago, underscoring the party’s new strength with union voters and suburban white women. For Democrats, the state was a key brick in its once stable “blue wall” of Northern swing states, and Hillary Clinton’s defeat there was a devastating electoral and psychological blow.

To win back the state, Democrats are not so much trying to flip counties that went for Mr. Trump in 2016, as they are doing in some other swing states. Instead, the focus is on whether voters who back Mr. Biden can prevent Mr. Trump from running up the score in white, working-class areas as he did in 2016. If Mr. Biden can cut into Mr. Trump’s margins in these areas while putting up big numbers in suburbs and cities, officials say his odds of winning the state look pretty good.

Of course, the Trump campaign has been doing all it can to hinder Mr. Biden from doing just that. In addition to its frenzy of activity, his campaign is also pursuing multiple strategies that would effectively suppress mail-in votes in the state.

There is a good chance Pennsylvania could hold the nation’s attention far after Election Day. Analysts don’t expect all of the mail-in ballots to be in until the later part of this week, meaning there most likely won’t be a winner called on election night. Even when the results are known, both parties are bracing for potential litigation.

You could be forgiven for feeling déjà vu after looking at Ann Selzer’s latest poll of Iowa.

The survey, released Saturday, showed a late shift toward President Trump, after months in which he and Joseph R. Biden Jr., the Democratic presidential nominee, had been running neck-and-neck in her polling of the state.

The most respected political polling operation in Iowa, Selzer & Company was the rare firm to pick up on the last-minute shift in support…