O'Rourke will start Thursday morning by delivering a 9:15 a.m. ET speech from El Paso that his campaign is billing as one in which he will "outline the path forward for his presidential campaign and for the future of the country."

Aides did not say where O'Rourke's next public appearance after the Thursday speech will take place.

O'Rourke left the campaign trail following an appearance at a forum in Nevada on August 3 amid news of the mass shooting, in which police say the alleged gunman was a white supremacist who left a screed complaining of a "Hispanic invasion."

Since then, he has sought to rally his heavily Hispanic hometown on the US-Mexico border, casting it as one that is welcoming to migrants. He has also harshly criticized President Donald Trump , calling him a white supremacist and saying his rhetoric targeting immigrants has inspired a rise in hate crimes and efforts to target immigrants.

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