Rusty Bowers, the speaker of the Arizona House, faced intense pressure from Trump allies.

The speaker of the Arizona House of Representatives, Rusty Bowers, who was the focus of an intense pressure campaign by President Donald J. Trump’s allies after the 2020 election, will tell his story publicly for the first time at the Jan. 6 hearing on Tuesday.

Parts of Mr. Bowers’s experience have been revealed previously: Mr. Trump and Rudolph W. Giuliani, the president’s personal lawyer, called Mr. Bowers as part of their efforts to undo Joseph R. Biden Jr.’s victory.

Mr. Bowers, a Republican, resisted that pressure, as well as efforts from another Trump ally to enlist him in a scheme to reject the certification of the Electoral College votes on Jan. 6, 2021.

In his testimony before the House committee investigating the Capitol attack, Mr. Bowers is expected to lay out details of the pressure he faced as well as of the threats that his family endured because he would not go along with what was asked of him.

Ahead of Mr. Bowers’s appearance, Mr. Trump issued a statement trying to undermine the lawmaker before he testified.

Mr. Bowers, who has said he voted for Mr. Trump, comes from a state that was called for Mr. Biden on election night by Fox News and, a few hours later, by The Associated Press. That the state was declared for Mr. Biden infuriated Mr. Trump’s aides.

This year, Mr. Bowers was given the John F. Kennedy Profile in Courage Award for his handling of the pressure campaign. Other recipients included Representative Liz Cheney, Republican of Wyoming and the vice chairwoman of the Jan. 6 committee, and Shaye Moss, an election worker in Georgia who is also scheduled to testify before the panel on Tuesday.