Biden and Harris Make New Push to Strengthen Support From Black Voters

President Biden and Vice President Kamala Harris are traveling to Philadelphia on Wednesday to announce the rollout of a new coalition aimed at bolstering support from Black voters, who are vital to their re-election but have broadcast frustration with the president in a series of polls.

The president and vice president will unveil the effort, Black Voters for Biden-Harris, during a rally at Girard College, a predominantly Black college preparatory school in Philadelphia. They will be joined by several prominent Black Democrats, including Lt. Gov. Austin Davis of Pennsylvania, Gov. Wes Moore of Maryland and Mayor Cherelle Parker of Philadelphia.

After the rally, dozens of Black leaders will embark on a nationwide “week of action” to mobilize Black voters in battleground states, according to the Biden campaign. The campaign also says it plans to team up with national groups to hold events, recruit surrogates and speak directly to Black communities through November.

The event is only the latest attempt by the Biden campaign to win back support from Black voters, who have long been known as the “backbone” of the Democratic Party.

This month, Mr. Biden delivered the commencement address at Morehouse College, a historically Black men’s college in Atlanta, and then flew to Detroit to speak at the largest N.A.A.C.P. dinner in the nation. Last week, Ms. Harris spoke in Philadelphia at a convention of the Service Employees International Union, one of the country’s most diverse labor unions

The Biden campaign also released a television ad last week that was geared toward Black voters in battleground states and that accused former President Donald J. Trump of having “stood with violent white supremacists.”

But even in Philadelphia — a