Russia’s meddling in last year’s presidential election reached unprecedented levels — with Donald Trump “egging on” the electronic hacking — and will threaten this country’s democratic foundation if not staunched, Democrat Rep. Adam Schiff told a full house Tuesday at UC Irvine’s Barclay Theatre.

Since Trump’s election, the ninth-term Burbank congressman has risen in prominence for his role as top Democrat — and most visible Trump critic on the House Intelligence Committee, which is investigating Russian interference in the election and Russian ties to those associated with the president.

“You can see all the reasons the Russians would like Donald Trump,” said Schiff, pointing to Trump campaign statements that attacked NATO, called for warmer Russian relations and praised Britain’s exit from the European Union. He went on to cite Russia’s role in releasing Democratic Party documents and in manipulating social media during the campaign.

“Beneath all of this was an underlying desire to undermine our democracy,” he said. “You had a candidate willing to accept the intervention. If the candidate had been John McCain or Mitt Romney, they would have rejected that. They would have said, ‘Butt out.’ … We have to show that we won’t stand idly by while they try to tear down our democracy and others around the world.”

Schiff said a movement toward authoritarianism in this country is reflected by Trump’s willingness to overlook human-rights abuses abroad and his friendly attitude toward controversial autocratic leaders in Russia, Turkey, the Philippines and Egypt.

“Our real agenda has to include a dedication to democracy and human rights,” he said.

The crowd of 600 gave Schiff a hearty standing ovation. But those on hand included a few who weren’t buying his pitch — including Irvine’s Dick Ackerman, a former state Senate GOP leader who served in the state Legislature with Schiff in the late 1990s.

“They don’t realize they’re are a lot of people like me who thought Barack Obama was destroying the country as we know it,” Ackerman said. “Barack Obama didn’t make human rights a major issue. … The Russians may have meddled in the election but they had no effect on the outcome.”

As for Trump egging on the Russians — during the campaign, he said, “Russia, if you’re listening, I hope you’ll be able to find the 30,000 emails that are missing” — Ackerman was equally dismissive, saying the candidate was joking.

“Democrats have no sense of humor,” he said. “Trump does.”

Schiff, a former federal prosecutor, was elected to Congress in 2000, when Democrats targeted Republican incumbent Jim Rogan because of his prominent role in the impeachment of Bill Clinton. While that was a high-profile race, Schiff subsequently took on a workman-like reputation until Trump’s election.

“I feel my role has changed,” he said during the second half of his Barclay Theatre appearance, when he was interviewed by UCI Law School Dean Erwin Chemerinsky. “I didn’t go to Washington to throw bombs. I’m not a bomb thrower. But I feel different about this presidency. I feel this presidency is shaking the foundation of this country. I have a responsibility.”

Schiff’s recent rise in the public eye, which includes a steady stream of TV and radio appearances that shows no sign of slowing, has transformed him into a likely leading candidate for the seat of California Sen. Dianne Feinstein, 83, should she choose not to seek re-election next year. Feinstein has not announced her plans, though she’s raised $650,000 this year and has $3.1 million in her campaign account.

Although he expects the Trump administration will push for a quick conclusion, Schiff anticipates the House investigation will not be wrapped up soon. He also said it’s important that the report be bipartisan — if not, Republicans will believe the GOP report and Democrats will believe the Democratic report.

“It’s a big investigation that has global reach,” he said. “It’s a very complicated investigation. … It’s obvious to everyone except the president that Russia interfered in the election.”

Future Russian efforts to affect U.S. elections are a near certainty, with the country’s vulnerability dependent on the public’s level of awareness and its determination to reject such interference, he said.

“On the Democratic side of the aisle, we failed to explain to the American people why it mattered,” Schiff said. “The only real defense is to inoculate ourselves, to understand what the Russians are doing. … The real power is in public opinion. We need the public’s sustained engagement.”