House Democrats begin the public portion of their push to impeach President Donald Trump this week with what they say is a powerful case that the president used his office for personal political gain — but they face a high-stakes challenge to convey that to a sharply divided public.

The House Intelligence Committee has its first impeachment hearings scheduled for Wednesday and Friday following weeks of closed-door depositions. The witnesses testifying in the open come from the same roster of unknown diplomats and bureaucrats who in their private interviews detailed complex matters of foreign diplomacy that are unfamiliar to most Americans.

As the inquiry into Trump’s dealings with Ukraine grew, so did the areas Democrats need to show where they think the president crossed a line. The politics of military aid to a foreign government, norms of diplomatic communications, foreign lobbying and legal terms such as quid pro quo and hearsay have created a tangled web of narratives on cable news and social media.

Democrats have yet to reveal a strategy to cut through those complicated issues — and the vigorous defense from Trump and his congressional supporters — in a way that succinctly explains why Trump should be removed from office for what they say is, at its heart, an “abuse of power.”

[Who’s holding the impeachment hearings?]

The party has been using that phrase to describe Trump long before Speaker Nancy Pelosi, D-Calif., on Sept. 24 announced an impeachment inquiry focused on whether Trump pressured Ukraine to open investigations into his political rivals.

While polling showed public support for impeachment grew in the two weeks following Pelosi’s announcement, it’s remained largely stagnant since then and even shown a slight decline over the past week, according to FiveThirtyEight’s average.

The polling only underscores the difficult task at hand for Democrats — most of whom have already made up their minds that Trump should be impeached — as they prepare to vote on articles of impeachment as soon as December.

No filter

The public hearings provide Democrats an opportunity to sharpen their message. Some members of the Intelligence Committee used the Sunday political talk shows to practice.

“Read the transcripts or watch it live and make up your own minds,” Rep. Sean Patrick Maloney, D-N.Y., said on “Fox News Sunday.” “You won’t have any filter. You won’t have the press or politicians in the way. You’ll have witnesses giving opening statements.”

Fellow Intelligence member Jim Himes urged his colleagues to stop using complicated terms like “quid pro quo” to explain “something that is really pretty simple.”

“Quid pro quo is one of these things to muddy the works,” the Connecticut Democrat said, arguing that “extortion” is a better term because it captures the simplicity of someone using their power to try to get something they don’t have a right to.

“The president acted criminally and extorted, in the way a mob boss would extort somebody, a vulnerable foreign country,” Himes said.

Democrats have pointed to a July 25 phone call in which Trump told Ukraine’s new president Volodymyr Zelenskiy, “I would like you to do us a favor,” as he asked him to investigate unfounded allegations that Ukraine interfered in the 2016 election, as well as the business dealings of Hunter Biden, the son of a main political rival, former Vice President Joe Biden.

In the public hearings Democrats will reveal a much broader Trump administration pressure campaign. They have witnesses who will testify that Trump withheld $400 million in U.S. security assistance to Ukraine as it was being attacked by Russia — as well as a promised White House meeting with Zelenskiy — to leverage Ukraine into opening the politically motivated investigations.

Trump, leading his own impeachment defense, has adopted “no quid pro quo” as part of his messaging. The president’s defenders in Congress have also used the Latin phrase, literally translated as “this for that,” in claiming there was no wrongdoing because Ukraine got the money without announcing an investigation.

The first witnesses to testify publicly on Wednesday — William Taylor, a longtime diplomat and the U.S. envoy to Ukraine, and George Kent, the deputy secretary of State for Europe — both said during their depositions that they understood the military aid and a White House meeting Trump promised Zelenskiy to be contingent on the investigations.

Republicans have sought to undermine Taylor and Kent’s accounts by noting neither had firsthand information. Indeed, the two State Department witnesses said they did not speak directly with Trump about the aid. Rather, their accounts rely on discussions with Gordon Sondland, the U.S. ambassador to the European Union.

“Ambassador Sondland tried to explain to me that President Trump is a businessman,” Taylor said. “When a businessman is about to sign a check to someone who owes him something, he said, the businessman asks that person to pay up before signing the check.” Procedural objections

The impeachment hearings will be different than the normal five-minute-per-member question-o-ramas. Democrats adopted rules that allow Intelligence Chairman Adam B. Schiff, D-Calif., or his staff to question the witnesses for 45-minute chunks, alternating with the minority for the same amount of time.

But Republicans likely will try to throw up any procedural obstructions and objections they can. Some Democrats believe that’s why GOP leaders have temporarily appointed Rep. Jim Jordan, R-Ohio, one of Trump’s most vocal defenders, to the Intelligence panel for the duration of the impeachment proceedings. Jordan, the top Republican on the Oversight Committee, has been leading the minority during the closed-door impeachment inquiry depositions.

Although Republicans had clamored for the proceedings to be conducted in the open, they have several complaints about how Democrats have structured the hearings. For one, they say, Trump’s lawyers can’t participate in Intelligence Committee hearings. They also argue that Democrats can veto their requested witnesses, such as the whistleblower whose complaint launched the impeachment inquiry.

Intelligence member Eric Swalwell, D-Calif., said Sunday on CBS’s “Face the Nation” that if Republicans try to raise procedural objections, “those stunts will be used by the American people against them to show a consciousness of guilt and a lack of seriousness.”

Republicans argue it’s the Democrats who aren’t being serious as they try to rush through the impeachment process.

“If we’re interested in trying to uncover the truth, then let’s not put our thumb on the scale,” Intelligence member Will Hurd, R-Texas, said on “Fox News Sunday.” “But unfortunately, that’s what this process has been. And what’s even crazier is they’re trying to have this completed by the end of the year, and I think we only have 16 or 17 legislative days left in the year.”

Former Rep. Tom Coleman, R-Mo., said Democrats would be wise not to get bogged down in the process arguments.

“The rules allow some clownishness, but you have to limit it as much as you can and not let them take your eye off the ball,” he said.

Former members of Congress have said Democrats also need to find a way to focus on getting some Republicans to their side. No Republicans voted for the resolution that set the rules for public hearings.

Trump, who has a knack for overwhelming the news cycle, has some counter-programming ready.

He’s planned a news conference Wednesday afternoon with Turkish President Recep Tayyip Erdogan. Their White House meeting will steal some energy from the impeachment hearings, since it comes a month after Trump’s controversial move to pull back U.S. forces supporting the Kurds fighting Turkey in Syria.