Pence pressure campaign from Trump the focus at Jan. 6 committee today

The Jan. 6 congressional committee is set Thursday afternoon to plunge into Donald Trump's last-ditch effort to salvage the 2020 election by pressuring his vice-president Mike Pence to reject the electoral count — a highly unusual and potentially illegal strategy that was set in motion in the run-up to the U.S. Capitol riot.

With two live witnesses Thursday, the House panel intends to show how Trump's false claims of a fraudulent election left him grasping for alternatives as courts turned back dozens of lawsuits challenging the vote.

Trump, after weeks of publicly refusing to accept the result, latched onto conservative law professor John Eastman's obscure plan and launched a public and private pressure campaign on Pence days before the vice-president was to preside over the Jan. 6 joint session of Congress to certify Joe Biden's election victory. A federal judge has said it is "more likely than not" Trump committed crimes over the scheme.

The committee will hear from Greg Jacob, the vice-president's counsel who fended off Eastman's ideas for Pence to carry out the plan; and retired federal judge Michael Luttig, who called the plan from Eastman, his former law clerk, "incorrect at every turn."

The panel could possibly present portions of testimony from Pence's former chief of staff, Marc Short, who testified under subpoena for eight hours.

The session Thursday is expected to divulge new evidence about the danger Pence faced that day as the mob stormed the Capitol shouting "hang Mike Pence!" with a gallows.

Along with hundreds of members of Congress on that day, Pence was forced to seek safety in the uncertain hours after the attack began, though he is said to have refused the option of being ushered away from the grounds by the Secret Service.

As the committee has teased in recorded interviews in the past week, Pence, not Trump, reached out to the Pentagon to have reinforcements sent to quell the insurrection. After the chaos subsided, Pence reconvened the ceremonial electoral count process, and officially certified Biden's win and Trump's defeat at just after 3:40 a.m. on Jan. 7.

The session Thursday will also unpack the Eastman plan to have alternative slates of electors sent from the five or seven states Trump was disputing, including Arizona, Georgia, Michigan, Pennsylvania and Wisconsin. With competing slates for Trump or Biden, it was hoped that Pence would be forced to reject them, returning them to the states to sort it out, under the plan.

Pence refused the plan.

With 1,000 interviews and reams of 140,000 documents, the committee is illustrating how Trump's false claims of election fraud became a battle cry for thousands of Americans to head to Washington to attend a Jan. 6 rally and then descend on Capitol Hill to "fight like hell" for his presidency. Ashli Babbitt, a Trump supporter, was shot to death by Capitol Police while part of a mob trying to gain access to a corridor.

WATCH | Trump's attorney general pushes back and other highlights from the last session:

More than 800 people have been arrested in relation to the Capitol siege, while members of extremist groups the Proud Boys and the Oath Keepers face rare sedition charges.

Two former White House aides under Trump, Steve Bannon and Peter Navarro, are facing criminal proceedings for defying subpoenas from the Jan. 6 committee.