The more concrete the testimony in the impeachment inquiry, the more solidly Republicans are sticking with President Donald Trump.
Witness after witness in closed-door House hearings is corroborating the core facts that Democrats say make a strong case against the president.
Trump pressured Ukraine, an American ally, for an investigation of Joe Biden, his family and the Democrats. At the same time, the Trump administration withheld military assistance for the young democracy as it confronted Russian aggression.
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For Democrats, it adds up to a nothing short of a brazen abuse of power, a quid pro quo, swapping U.S. foreign policy and funds for personal political gain
"I don't think there is any justifying this president's misconduct," Rep. Adam Schiff, the chairman of the Intelligence Committee leading the inquiry said in an interview.
Republicans are having none of it. Trump says it's all just a "witch hunt," and his supporters agree.
"The American people see this for what it is," said Rep. Jim Jordan of Ohio, the top Republican on the Oversight committee that's part of the inquiry. "We see it just like the American people do, and we know -- we just know -- it's wrong."
While that investigation unfolds in the basement of the Capitol, another version plays out upstairs for the public.
House Speaker Nancy Pelosi gaveled a vote this week to formalize the impeachment inquiry, and the roll call split along predictable party lines.
Not a single Republican joined Democrats to agree to investigate. Among the Democrats, all but two stuck together to support the inquiry.
In previous modern-era impeachment proceedings, at least some lawmakers crossed party lines to initially provide bipartisan support for the probes of Richard Nixon and Bill Clinton.
But times are different now. The polarizing of the country plays out in almost all aspects of political life. Impeachment proceedings, so far, are only reflecting that divide, in Congress as in the country at large.
More Americans approve than disapprove of the impeachment inquiry, 47% to 38%, according to a new poll by The Associated Press and the NORC Center for Public Affairs Research. But it all depends on whom you ask.
The vast majority of Democrats approve of the inquiry, 68% of them strongly. Most Republicans disapprove, 67% strongly.
Neither Trump nor Republicans in Congress dispute the White House's rough transcript of Trump's July phone call with Ukrainian President Volodymyr Zelenskiy. They say it proves the president did nothing wrong.
Standing before a portrait of George Washington after the House vote, the GOP leader, Kevin McCarthy of California, quoted Pelosi from earlier this year saying impeachment was "so divisive for the country" she'd rather not pursue it unless it was completely necessary.
"What has changed?" McCarthy asked. "In all the hearings there's nothing compelling, nothing overwhelming." He said it's a "sham that has been putting the country through this nightmare."
Pelosi, in an interview Friday with Bloomberg News, said it was the phone call between Trump and the Ukrainian president that "changed everything in the public mind."
Pelosi launched the impeachment inquiry after a government whistleblower recounted that Trump in the call asked Zelenskiy for "a favor."
Trump insists the conversation was "perfect."
Julian Zelizer, a professor at Princeton University, said partisanship is greater than it was during Watergate and "the loyalty to party even greater."
Thus, there isn't likely to be any group of Republican lawmakers heading to the White House to tell the president it's over, as happened during the impeachment proceedings against Nixon. No march of Republicans to say that support for Trump has dwindled and they can no longer protect him.
As for this week's solid House support, Schiff said, "I think it's a vote they will come to regret over time."
"And I think when their children and grandchildren ask what they did to stand up to this unethical president ... they will have a hard time explaining why they chose to defend him."
It's specifically illegal to seek or receive foreign assistance in U.S. elections. But the framers of the Constitution drafted the impeachment clause more broadly, capturing all level of "high crimes and misdemeanors" that could be committed in the White House.
While the first president, Washington, was seen as a leader beyond reproach, the founders knew not all who followed might be.
There could be those who sought to use the office for personal financial gain or to rule the country more like the monarchy the founders were leaving than the democracy the U.S. was becoming. And so they tucked in the impeachment provision as part of the simple, but powerful, system of checks and balances among the three branches of government.
The system depends on an agreement not only of the facts but of what the facts mean.
Zelizer, who favors impeachment, says that back in 1974, "nobody would have expected Republicans" to go to the White House as they did to pressure Nixon to resign.
But once the evidence spilled out about what Nixon said in his taped recordings, the situation became indefensible for Republicans. It's hard not to wonder if that would ever happen again.
So far in this era of intense partisanship, Republicans are rock solid in supporting Trump. House investigators are now preparing to push the impeachment hearings into the open.
Associated Press writers Mary Clare Jalonick and Hannah Fingerhut contributed to this story.