Georgia Secretary of State Brad Raffensperger and his top deputy Gabriel Sterling will testify at Tuesday's hearing of the House Select Committee to Investigate the January 6th Attack on the United States Capitol, to shine more light on one of the more brazen attempts to overturn the 2020 election.

Their planned testimony is confirmed by sources familiar with Tuesday’s hearing but not authorized to speak publicly before the committee announces its schedule.

Raffensperger famously rebuffed former President Donald Trump's pressure to "find" enough votes to reverse his narrow election defeat, and Sterling was a frequent figure on televised news conferences debunking false claims of fraud and fellow Republicans' attacks on election workers.

In last month's primary elections, Raffensperger defeated Trump-backed challenger Rep. Jody Hice.

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Tuesday's committee hearing is expected to highlight the pressure campaign that Trump and his allies exerted on local elections officials in Georgia and other states to reverse the presidential election results, and comes on the heels of a hearing Thursday that outlined attempts to get former Vice President Mike Pence to reject the Electoral College results. 

The Georgia officials' public testimony comes after Raffensperger appeared recently in a closed-door special grand jury investigation in Fulton County that is seeking to determine if Trump and others violated several state laws in their efforts to overturn the 2020 presidential election.

Raffensperger and others have also provided hours of testimony privately to the committee, including discussion of the unprecedented call from Trump, leaked to GPB NewsThe Washington Post and other outlets in the runup to Georgia's dual U.S. Senate runoffs.

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Georgia's politics have remained central to understanding how thousands of Trump supporters attacked the Capitol in hopes of blocking the certification of Joe Biden as president, ranging from fraudulent "alternate electors" submitted by top Republican officials, numerous failed lawsuits and harassment of election workers in efforts to find widespread fraud that three separate counts of the votes confirmed was not present. 

Other notable moments include Trump's call to the state's top election investigator encouraging her to uncover absentee ballot fraud in a review of envelope signatures (that ultimately found no invalid ballots) and presentations to state lawmakers riddled with errors and false claims encouraging them to reject election results.