The ex-president is expected to deliver closing remarks on the last day of the two-day America First Agenda Summit on July 26, a conference hosted by a pro-Trump group.
Trump's speech comes as the House of Representatives committee probing the Jan. 6, 2021, insurrection continues to hold hearings digging into the events of that day, during which Trump's supporters stormed the US Capitol in a bid to prevent President Joe Biden from assuming office.
The House panel is slated to hold its next hearing July 21 following bombshell revelations from Republican lawmaker Liz Cheney that Trump attempted to contact one of the committee's witnesses. The matter has been handed to the Justice Department for a potential witness tampering investigation.
Polling released Tuesday suggests that the former president's hold on his party may be loosening with more than half of the party's primary voters now aligning behind different presidential candidates.
Still, Trump holds 49% of the party's support, according to the New York Times/Siena College poll. But support is particularly weak among Republicans aged 35 and younger, as well as those with college degrees.
About 20% of respondents said they believe Trump "went so far that he threatened American democracy" when he attempted to hold on to power after suffering a major electoral defeat to Biden, losing by 7 million votes.
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