Schiff warns of Russian attack on US mainland, as Day 2 of Trump's Senate impeachment trial concludes

House Democrats launched into lengthy arguments that broke little ground, if any, in President Trump's impeachment trial Wednesday -- as the head impeachment manager, California Rep. Adam Schiff, suggested that Russians could attack the U.S. and insisted that removing Trump from office was necessary because the integrity of the 2020 election could not be "assured."

Trump's lawyers sat by, waiting their turn, as the president blasted the proceedings from afar, threatening jokingly to face off with the Democrats by coming to "sit right in the front row and stare at their corrupt faces."

The challenge before the House managers has been clear. Democrats were given 24 hours over three days to prosecute the charges against Trump, trying to win over not just fidgety senators sitting silently in the chamber but an American public, deeply divided over the president and his impeachment in an election year.

Most senators sat at their desks throughout the day, as the rules stipulated, though some stretched their legs, standing behind the desks or against the back wall of the chamber, passing the time. Visitors watched from the galleries, one briefly interrupting in protest.

Almost immediately after Chief Justice John Roberts gaveled in Wednesday's session, bored and weary senators started openly flouting some basic guidelines. Fox News observed that a Democrat in the back row leaned on his right arm, covered his eyes and stayed that way for nearly a half-hour, and some lawmakers openly snickered when Schiff said he'd speak for only 10 minutes.

INSIDE THE CHAMBER, RESTLESS LAWMAKERS STRUGGLE TO PAY ATTENTION AS SENATE TRIAL DRAGS ON

"I do see the members moving and taking a break," freshman Rep. Jason Crow, D-Colo., one of the House prosecutors, said mid-speech at the center podium. "I probably have another 15 minutes."

"You just have to stretch and you just got to stand. Those chairs, they look nice, [but] they are not comfortable chairs," Sen. Lisa Murkowski, R-Alaska, a key swing-vote moderate, said of the restlessness while Schiff spoke.

The previous day of the trial lasted for more than 12 hours, and ended well past midnight on a testy note as Roberts admonished both sides for their conduct. On Wednesday, Murkowski slammed Democratic impeachment manager Rep. Jerry Nadler, D-N.Y., for arguing the previous evening that senators who didn't vote for immediate subpoenas were defying their oaths of office: “As one who is listening attentively and working hard to get to a fair process, I was offended," Murkowski said.

Perhaps sensing the ennui in the chamber on Day 2 of the trial, Schiff, the chairman of the House Intelligence Committee, sought to keep the stakes high. He suggested at one point that military aid to Ukraine was essential so the U.S. would not have to fight Russians at home, as soldiers did in the videogame "Call of Duty: Modern Warfare 2."

"As one witness put it during our impeachment inquiry, the United States aids Ukraine and her people so that we can fight Russia over there, and we don't have to fight Russia here," Schiff said, drawing rebukes from commentators across the political spectrum.

"Liberals used to mock Bush supporters when they used this jingoistic line during the war on Iraq," wrote journalist Max Blumenthal. "Now they deploy it to justify an imperialist proxy war against a nuclear power."

Schiff attracted the most criticism, however, for later making the head-turning argument that Trump must be removed from office by the Senate -- rather than by voters in the 2020 election -- because it is impossible to be sure the 2020 election won't be compromised.

"The president's misconduct cannot be decided at the ballot box, for we cannot be assured that the vote will be fairly won," Schiff remarked. He did not elaborate.

Constitutional scholar Alan Dershowitz, who will speak against impeachment, is expected to argue before the Senate that removing a president is a fundamentally undemocratic remedy that requires "criminal-like" conduct -- a standard he will argue is not met by Democrats' two articles of impeachment, which do not allege federal crimes.

But, both Republicans and left-of-center commentators didn't wait long to deride Schiff's incendiary arguments in more direct terms.

"And right here is proof of the Democrats’ plan all along," Trump campaign director of communications Tim Murtaugh said in response. "Every moment of the impeachment sham has been geared toward interfering with the 2020 election. Schiff is preemptively calling into question the results of an election that is still more than 9 months away."

Aaron Mate, a contributor at The Nation, added: "For all the talk about Russia undermining faith in US elections, how about Russiagaters like Schiff fear-mongering w/ hysterics like this? Let's assume Ukraine did what Trump wanted: announce a probe of Burisma. Would that delegitimize a 2020 US election? This is a joke."

And during the proceedings, Trump retweeted a post from Kentucky GOP Sen. Rand Paul: "The more we hear from Adam Schiff, the more the GOP is getting unified against this partisan charade." Trump added, "True!"

Meanwhile, the Republican House leader, California Rep. Kevin McCarthy, suggested during the day that Schiff should be censured by the House for constantly lying, including by apparently misrepresenting key documents from Lev Parnas, a Giuliani associate.

Schiff, though, was undeterred. Attempting to underscore the human cost of Trump's temporary aid holdup, Schiff further asserted that the money was "designed to help Ukraine defend itself from the Kremlin's aggression" and that "more than 15,000 Ukrainians have died fighting Russian forces and their proxies."

CHIEF JUSTICE ROBERTS ADMONISHES BOTH SIDES AS IMPEACHMENT TRIAL DAY 1 TURNS INTO SHOUTING MATCH

Republicans erupted when Schiff made a similar argument during last year's House impeachment probe. Trump's lawyers were likely to fire back when it's their turn to present arguments -- in part because former President Obama provided less aid to Ukraine than the Trump administration has.

Additionally, Republicans have pointed out that the temporary lack of aid has not been directly linked to any casualties, and that the U.S. cannot reasonably be held responsible for the actions of Russian-backed militants in Ukraine.

Schiff also repeatedly made the false claim that White House chief of staff Mick Mulvaney had said people should "get over" the idea that Trump was tying foreign aid to political investigations. Mulvaney, in fact, had remarked only that politics and foreign policy sometimes overlap.

Schiff, who had previously claimed to have evidence that the Trump campaign secretly colluded with Russia, was outlining what the Democrats contended was the president's "corrupt scheme" to abuse his presidential power and then obstruct Congress' investigation.

He called on senators not to be "cynical" about politics, but to draw on the intent of the nation's Founding Fathers who provided the remedy of impeachment.

"Over the coming days, we will present to you—and to the American people—the extensive evidence collected during the House’s impeachment inquiry into the president's abuse of power," Schiff argued. "You will hear their testimony at the same time as the American people. That is, if you will allow it."

The proceedings were unfolding at the start of an election year, and there have been few signs that Republicans were interested in calling more witnesses or going beyond a fast-track assessment likely to bring a quick vote on charges related to Trump's dealings with Ukraine.

Some Democrats sounded a note of concern that Republicans haven't expressed much interest in crossing the aisle concerning witness and document requests. "I can only speak for myself: strikingly little," Sen. Chris Coons, D-Del., said after the proceedings adjourned, when asked how much Republican outreach he has seen.

SCHIFF HAMMERED FOR MISREPRESENTING "MR. Z" PARNAS EVIDENCE, AS WELL AS CLAIMING RUSSIA WILL CONTROL THE 2020 ELECTION

The trial has marked just the third time the Senate has weighed whether an American president should be removed from office. Democrats argued Trump abused his office by asking Ukraine to investigate political rival Joe Biden while withholding crucial military aid, and also obstructed Congress by refusing to turn over documents or allow officials to testify in the House probe.

Republicans have defended Trump's actions and cast the process as a politically motivated effort to weaken the president in the midst of his reelection campaign. Specifically, Republicans have pointed out that Ukrainian leaders said they felt no undue pressure; that the longstanding constitutional executive privilege shielded the White House from having to respond to comprehensive subpoenas; and that the Democrats' case was based largely on hearsay.

Trump's legal team also has argued that Democrats' impeachment case couldn't be as "open-and-shut" as advertised given the apparently urgent need for new evidence even after the House impeachment inquiry.

In any event, the White House has said Trump's suggested probe into Biden was appropriate.

new poll from The Associated Press-NORC Center for Public Affairs Research showed the public was slightly more likely to say the Senate should convict and remove Trump from office than to say it should not, 45 percent to 40 percent. But, a sizable percentage, 14 percent, said they didn't know enough to have an opinion.

WHOOPS: BIDEN CAMPAIGN CITES UKRAINIAN ACTIVIST WHO SAID HUNTER BIDEN DID 'VERY BAD THING' IN UKRAINE

One question on which there was wide agreement: Trump should allow top aides to appear as witnesses at the trial. About 7 in 10 said so, including majorities of Republicans and Democrats, according to the poll.

The strategy of more witnesses, though, seemed all but settled. Wrangling over rules for the trial stretched past midnight Tuesday night, with Republicans shooting down one-by-one Democrats' efforts to get Trump aides including former national security adviser John Bolton, Secretary of State Mike Pompeo, and acting chief of staff Mick Mulvaney to testify.

Senators are likely to repeat those rejections next week, shutting out any chance of new testimony.

One longshot idea to pair one of Trump's preferred witnesses — Biden's son Hunter — with Bolton or another whom Democrats wanted was swiftly rejected.

"That's off the table," Senate Minority Leader Chuck Schumer, D-N.Y., told reporters.

Trump, who was in Davos, Switzerland, attending a global economic forum, praised his legal team and suggested he would be open to his advisers testifying, though it seemed unlikely. He said "national security" concerns would stand in the way.

After the House prosecutors present their case, the president's lawyers are set to follow with another 24 hours over three days. They are expected to take only Sunday off.

"There's a lot of things I'd like to rebut," Trump lawyer Jay Sekulow said at the Capitol, "and we will rebut."

Sekulow also said that he thought it was unlikely that Democrats would meet the threshold necessary to demonstrate the need for additional witnesses, but that the Trump team was preparing for every contingency.

Then there will be 16 hours for senators, who must sit quietly at their desks, no speeches or cellphones, to ask written questions, and another four hours for deliberations.

The impeachment trial is set against the backdrop of the 2020 election. All four senators who are presidential candidates have been off the campaign trail, seated as jurors.

Campaigning at stops in Iowa, Joe Biden also rejected having his son testify, or even appearing himself. "I want no part of that," he said.

"People ask the question, isn't the president going to be stronger and harder to beat if he survives this? Yes, probably. But Congress has no choice," Biden added, saying senators must cast their votes and "live with that in history.”

Some Republicans expressed disdain for it all.

Iowa GOP Sen. Joni Ernst spoke sarcastically about how excited she was to hear the "overwhelming evidence" the House Democrats promised against Trump. "Once we've heard that overwhelming evidence," she added, raising her voice mockingly, "I don't know that we'll need to see additional witnesses, but let's hear about that overwhelming evidence."

The trial began with an apparent setback on Tuesday for Republican Senate leader Mitch McConnell, who backed off his plans to limit each side's arguments to two days, as the White House had preferred.

But, in a strong show of Republican unity, the GOP-led Senate repeatedly resisted Democrats' amendments to McConnell's rules, and ultimately approved a rules package pushing off a final decision on whether to seek additional testimony until late in the trial.

Schumer bemoaned the remaining limitations, saying Wednesday the impeachment trial "begins with a cloud hanging over it, a cloud of unfairness."

JIM JORDAN: THE FOUR FACTS DEMS CAN'T CHANGE

Republicans have been eager for a swift trial. Still, Trump's legal team passed on an opportunity to file a motion to dismiss the case on Wednesday, an acknowledgment that there were not enough Republican votes to support it.

The White House legal team, in its court filings and presentations, has not disputed Trump's actions, but the lawyers insisted the president did nothing wrong.

Fox News' Chad Pergram, Marisa Schultz, Adam Shaw and The Associated Press contributed to this report.