HARRISBURG — Vice President Pence will headline a July 23 fundraiser in Philadelphia for Pennsylvania's Republican candidate for the U.S. Senate in November, Rep. Lou Barletta.

Pennsylvania Republican Chairman Val DiGiorgio said he expects the event to raise from $300,000 to $400,000 for Barletta, who has badly trailed Democratic Sen. Bob Casey in campaign cash. The event will be at the Union League, a spokesperson for Barletta's senatorial campaign confirmed. The campaign did not elaborate on time or attendance details.

Casey is running for a third term. No independent poll puts Barletta within striking distance of Casey, but Barletta is a staunch supporter of President Trump and Republican officials expect Trump will come to Pennsylvania to campaign for Barletta. Trump extended public congratulations to Barletta after he won May's Pennsylvania Republican primary race, remarking on Twitter that Barletta "will be a great Senator and will represent his people well."

At the end of April, Barletta reported $1.3 million in the bank, compared with Casey's $10 million.

A Barletta fundraiser scheduled next week is being headlined by Nigel Farage, an architect of Britain's vote to leave the European Union.

Pence's visit to Philadelphia will be his second in recent months, after he participated in a fundraiser at the Rittenhouse Hotel alongside GOP gubernatorial nominee Scott Wagner in June.

At that event, the vice president was met by dozens of protesters who gathered in Rittenhouse Square, voicing general disapproval of the Trump administration and specifically its "zero tolerance" policy that separated children from parents attempting to cross into the United States. Trump, facing pushback, signed an executive order ending the policy.

>> READ MORE: Lou Barletta rolls with Trump, as president shifts policy at border

The administration has said that all eligible young children have been reunited, though nearly half of those under 5 remain separated from their families because of safety concerns or other issues.

Protests against the July 23 visit are being organized by Refuse Fascism Philly, Refuse Fascism, Delco NOW, Philly UP, and NextGen Pennsylvania.