Harris hopes to capitalize on Polish Americans' historic animosity toward Russia and on Trump's hesitancy to back Ukraine during last week's debate. The Democratic vice president's team organized a national call with Polish American supporters on Wednesday to encourage local networks to hold their own events and spread the campaign's message.

Both the Democratic and Republican parties have sought to engage Polish-Americans, a dependable voting demographic.

Polish Americans are an important, if politically overlooked, demographic. But in Pennsylvania, many have tended to lean Republican.