WASHINGTON - President Donald Trump is now expected to become only the third U.S. president impeached by the House of Representatives.
If the Democratic-controlled House votes next week to impeach Trump for allegedly abusing his power related to his dealings with Ukraine, the case would move to the Republican-controlled Senate for an impeachment trial where the political landscape is much more favorable to the president.
While Democrats dominate the House, Republicans hold 53 of the 100 seats in the Senate. Democrats hold 45, and also count on the votes of two independents - Angus King of Maine and Bernie Sanders of Vermont.
In order for Trump to be removed from office, the Senate, sitting as jurors, would need to convict him of one or more articles of impeachment by a two-thirds majority vote, or 67 of the 100 senators, according to the U.S. Constitution.
Republican-Led Senate Looms as Trump's Savior video player. Embed Copy Link
A high bar
Democrats would need to find a way to get 20 Senate Republicans to support conviction. Given polls that show Republican voters are still firmly behind the president, experts see Trump's removal as highly unlikely.
"I do not see how in the world you could ever get 20 Republican senators to vote to oust Donald Trump," said University of Virginia analyst Larry Sabato via Skype. "They might as well vote to oust and then announce their resignations, because they won't be serving for very long once they cast that vote."
While House Republicans have stood with the president on impeachment, a few Senate Republicans such as Mitt Romney of Utah and Susan Collins of Maine have been critical of the president at times.
Associated Press Washington bureau chief Julie Pace said those senators will be watched closely in a Senate trial.
"It does not mean that they will vote to convict him, but it does mean that we may see a scenario in which you have at least some members of Trump's party expressing real concern about his interactions with Ukraine."
What kind of trial?
There is also the issue of how a Senate impeachment trial will be conducted. As laid out in the U.S. Constitution, Chief Justice John Roberts would preside. But the Senate approves the rules for consideration of evidence and witnesses.
Trump has said he would like to call a host of witnesses, including Democratic House Intelligence Committee Chairman Adam Schiff, former Vice President Joe Biden, his son Hunter Biden, and the whistleblower who filed the initial complaint over the president's dealings with Ukraine.
House Democrats have accused Trump of abuse of power by demanding that Ukraine announce an investigation of the Bidens, and a discredited theory that Ukraine conspired with Democrats to interfere in the 2016 election in exchange for the release of $391 million in military aid that was temporarily held up by the White House.
White House officials expect the trial procedures will benefit the president. White House counselor Kellyanne Conway said Trump would be helped "where you get to introduce live witnesses and have them cross-examined, and introduce your own pieces of evidence, and challenge other people's evidence."
Senate Majority Leader Mitch McConnell and other Republicans are said to favor a shorter, streamlined trial that would not include witnesses. They would prefer to dispense of the impeachment case against Trump fairly quickly, perhaps in a few weeks. By contrast, the Clinton impeachment trial in 1999 ran for five weeks.
"I'm not in the camp of calling a bunch of witnesses. I think as an American, the best thing we can do is deep-six this thing," Republican Sen. Lindsey Graham told Axios.
Senate Minority Leader Chuck Schumer has warned Republicans against a partisan trial.
"The best way to do something as important and almost as hallowed a procedure as this is in a bipartisan way," the New York Democrat said.
That may not suit Trump, who reportedly wants to use impeachment as motivation to drive his supporters to the polls in next year's presidential election.
Trump has denied the allegations and is counting on Senate Republicans to vote to acquit him in an impeachment trial.
"The radical left Democrats and the failed Washington establishment are trying to erase your votes, nullify the election and overthrow our democracy," Trump told supporters this week at a campaign rally in Hershey, Pennsylvania. "It is not going to happen, don't worry about it."
A test for the Senate
The Senate has been down this road before.
In 1999, Clinton was acquitted of perjury and obstruction of justice related to his affair with White House intern Monica Lewinsky.
In 1868, President Andrew Johnson survived a Senate trial by a single vote after he was impeached for violating a congressional act protecting high government officials from removal.
In Trump's case, House Democrats have accused him of abuse of power for pressuring Ukraine to investigate the Bidens, and obstruction of Congress for ordering administration officials to refuse to testify or provide documents as part of the impeachment inquiry.
"Our president holds the ultimate public trust," said House Judiciary Committee Chairman Jerrold Nadler, as he introduced the two articles of impeachment. "When he betrays that trust and puts himself before country, he endangers the Constitution, he endangers our democracy, and he endangers our national security."
No matter the outcome, a Senate trial will be a demanding test for U.S. democracy.
"I would hope and pray that all of my Senate colleagues will take a deep breath no matter where we have been so far and step back and realize this is probably the most important constitutional responsibility we have," Democratic Sen. Mark Warner told reporters at the Capitol.
Perhaps looking ahead to a January trial, Senate Chaplain Barry Black offered up an appeal this week for divine guidance as the Senate was gaveled to order.
"Lord, guide our senators to the right paths. Lead them beside still waters. Restore their souls."