WASHINGTON, Jan 4 (Reuters) - The U.S. Congress" probe of the deadly Jan. 6 assault on the Capitol by Donald Trump supporters soon begins weeks of public hearings that will put the investigation in the spotlight as campaigning intensifies for the November elections. The probe into the worst attack on Congress since the War of 1812 has largely played out behind closed doors so far. The House of Representatives Select Committee on Jan. 6 has interviewed more than 300 witnesses about the violence by Trump supporters seeking to overturn his election defeat and Trump"s response to it. The committee"s members are racing to finish their work before elections on Nov. 8. The seven Democrats and two Republicans know their efforts could be shut down if Republicans take back a majority of the House as forecasters believe is likely. Media coverage of the hearings could become campaign fodder. House Republican leadership refused to take part in the probe as about 55% of Republican voters now believe former President Trump"s claims that his defeat was the result of widespread fraud. Multiple courts have rejected that contention but it has nonetheless spurred a wave of new state limits on voting. The House probe is moving in parallel to the Justice Department"s prosecution of about 725 accused rioters on charges ranging from disorderly conduct to conspiracy. About 165 people so far have pleaded guilty to taking part in the attack and the first trials could begin next month. Members of the House committee warn that the false claims of voter fraud that inspired the violence are also undermining faith in the U.S. democratic system. "Our democracy was inches from ruin," Representative Bennie Thompson, the committee"s chairman, said at a congressional hearing last month. "We want to figure out why and share that information with the American people." "TO HELL AND BACK" The Select Committee is tasked with investigating and reporting on what led to the attack, in which Trump supporters assaulted police, smashed windows and sent members of Congress and then-Vice President Mike Pence running for their lives. The committee is aiming to release an interim report in the summer of 2022 and a final report in the fall, a source familiar with the investigation said. "We will be conducting multiple weeks of public hearings, setting out for the American people in vivid color exactly what happened, every minute of the day on Jan. 6, here at the Capitol and at the White House, and what led to that violent attack," Republican Representative Liz Cheney said last month. The only public hearing so far, held in July, featured testimony from four police officers about the physical and verbal assaults they faced responding to Capitol riots. "I feel like I went to hell and back to protect the people in this room," said then-District of Columbia police officer Michael Fanone, referring to lawmakers. "The indifference shown to my colleagues is disgraceful," Fanone added, slamming his hand onto the witness table. Around 140 police officers were assaulted during the riot, according to the Justice Department. One officer who battled rioters died the day after the attack and four who guarded the Capitol later died by suicide. Four rioters also died, including one who was shot by police as she tried to climb inside the building through a shattered window. A CRIMINAL REFERRAL Trump has loomed large in the committee"s work since the beginning, and that focus has become more apparent in recent weeks. During a Dec. 13 hearing, Cheney read text messages sent by Trump supporters to his chief of staff, Mark Meadows, imploring the then-president to speak out against the violence. Cheney said the committee wants to ask Meadows: "Did Donald Trump, through action or inaction, corruptly seek to obstruct or impede Congress" official proceeding to count electoral votes?" Cheney was pointing to a specific statute — a felony in the U.S. criminal code — and suggesting Trump might have violated it. Ultimately, the Justice Department will decide whether to charge Trump, but the committee could issue a "criminal referral," increasing the political pressure on Attorney General Merrick Garland to act. In November the Justice Department charged Trump ally Steve Bannon with "contempt of Congress," a misdemeanor offense, after he defied a Select Committee subpoena for his testimony. Bannon has vowed to fight the charges, saying he has a lawful basis for declining to testify. The committee has recommended similar charges against two other Trump allies. Trump is separately under investigation by state prosecutors in Georgia over whether he unlawfully pressured election officials to change the vote tally in his favor.