Some Republican officials have stumbled in recent days in their attempts to defend Trump’s dealings with Ukraine, and others have pushed the White House to offer more guidance to its defenders by standing up a centralized, organized response effort.

Trump’s reelection campaign has taken a de facto lead role in hitting back against the president’s detractors, but it has not been specifically tasked with a coordinating role, according to a person familiar with the matter who, like others, discussed internal strategy on the condition of anonymity.

On Monday, Trump’s defenders faced new revelations, in a Washington Post story, that Attorney General William P. Barr has held private meetings overseas with foreign intelligence officials, seeking their help with his department’s inquiry into foreign interference in the 2016 election — a probe that Trump hopes will discredit the U.S. intelligence community’s conclusion that Russia sought to assist his campaign. It was also reported that the president used a recent phone call to ask Australian Prime Minister Scott Morrison to provide help to this ongoing Justice Department investigation. The Trump-Morrison phone call was first reported by the New York Times.

As he faces mounting accusations of wrongdoing, Trump is leading his own defense effort, largely from his Twitter account. He is using the kind of bluster and bravado that have come to define his presidency.

“The Fake Whistleblower complaint is not holding up,” he said Monday on Twitter, after lamenting “the Greatest Witch Hunt in the history of our Country!”

While the tactical logistics of Trump’s legal and political defense were still being sorted out, there was a sense of agreement among the president’s aides and allies that attacking his detractors would be a key part of the strategy.

“We are not on the defense for impeachment,” said one campaign official, who spoke on the condition of anonymity to discuss internal deliberations. “We are on offense to show the American people this is a coup d’etat by elitist bureaucrats and Democrats.”

White House press secretary Stephanie Grisham accused the media of “hysteria” and said Trump had “done nothing wrong” in a phone call in which he encouraged Ukraine’s president to investigate Biden and his son Hunter over the younger Biden’s former position with a Ukranian private gas company — an arrangement that Trump and his allies say was corrupt.

Hunter Biden served for nearly five years on the board of Burisma, whose owner came under scrutiny by Ukrainian prosecutors for possible abuse of power and unlawful enrichment. Hunter Biden was not accused of any wrongdoing in the investigation. As vice president, Joe Biden pressured Ukraine to fire the top prosecutor, Viktor Shokin, who Biden and other Western officials said was not sufficiently pursuing corruption cases. At the time, the investigation into Burisma was dormant, according to former Ukrainian and U.S. officials.

Rudolph W. Giuliani, Trump’s personal attorney, has taken a lead role in pushing Ukraine to investigate Biden as well as the theory that Ukrainians worked with Democrats to undermine Trump’s campaign in 2016. On Monday, the three House committees leading the impeachment effort issued a subpoena demanding that Giuliani turn over all records pertaining to his contacts regarding Ukraine, the Biden family and related matters.

The committees have also subpoenaed information from Secretary of State Mike Pompeo, who was scheduled to leave Monday night for a six-day trip to Italy, Montenegro, North Macedonia and Greece. He is not due to return until Sunday, meaning he will be out of the country when a Thursday deadline passes for the State Department to deliver to the House committees documents related to Trump’s July call with Ukrainian President Volodymyr Zelensky.

Jay Sekulow, Trump’s personal attorney, called the Democrats’ impeachment effort “absurd” and said that his team’s experience in dealing with special counsel Robert S. Mueller III’s extensive investigation of the Trump White House provided a template for how to handle the impeachment inquiry.

“We just went through a war without a war room, and that was the Mueller probe, and that worked out well,” he said, describing the impeachment probe as more of a “skirmish.”

Trump will be the chief messenger in the response effort, and his allies will probably take cues from him, said Sekulow.

Some Republicans say that’s the problem. In the past few days, Trump has called for the whistleblower to be unmasked, suggested that House Intelligence Committee Chairman Adam B. Schiff (D-Calif.) should be arrested for treason and amplified the comment of a supporter who said impeachment could create a “Civil War like fracture” in the United States.

Behind the scenes, the president is sounding out a range of advisers for different options, speaking to friends, outside confidants and Republican lawmakers to get advice about how to proceed, according to a senior administration official.

“There are different ways to bake the cake, depending on what sort of cake you want,” the official said. “Different flavoring, different temperatures, different ingredients yield different types of cake, and the president as the master baker is testing recipes and deciding what type of cake he wants.”

Some Republicans have pushed the White House to set up a more organized approach and have lamented that there’s no clear plan or strategy to follow.

“It’s such a cliche that Trump doesn’t think anyone can defend him the way he can defend himself, but they need to try, because right now it’s just him tweeting about Adam B. Schiff,” said a Republican congressional aide, who spoke on the condition of anonymity to discuss their view of the White House’s plan.

Trump’s reelection campaign, well capitalized from record fundraising and well-staffed after an early hiring effort, has taken a lead role in defending the president.

While the campaign has not been officially designated as the central engine of Trump’s impeachment response, it has sought to take the mantle as the best-equipped to do so, according to a person familiar with the matter. The campaign, which has been operating since the first day of Trump’s presidency, has the manpower and experience to mount a rapid-response effort complete with video content, talking points and campaign ads, said this person.

The Trump campaign released a television ad Friday that painted Democrats’ impeachment effort as an attempt to “steal” the election. The campaign said it was spending $10 million to air the ad on cable and online.

“The American people see this for what it is: yet another attempt by Democrats to disenfranchise the American people by removing a duly elected president that they disdain,” campaign spokeswoman Kayleigh McEnany said.

Trump allies are also considering running television ads that target roughly two dozen Democratic House members who won in districts that Trump carried in 2016, to argue that those members are not doing the work of the American people while they’re focused on trying to impeach the president. Marc Short, Vice President Pence’s chief of staff, is one of those supporting this idea.

In addition to attacking Democrats, the president will also need to keep Republicans on board, as GOP lawmakers have been far from united in defending Trump’s call with Zelensky.

Trump’s former homeland security adviser, Thomas Bossert, said Sunday that he was “deeply disturbed” by Trump’s conduct on the call.

“It is a bad day and a bad week for this president and for this country if he is asking for political dirt on an opponent,” he said on ABC’s “This Week.”

Rep. Adam Kinzinger (R-Ill.) said Sunday that it was “beyond repugnant” that Trump had raised the specter of civil war.

And House Minority Leader Kevin McCarthy (R-Calif.) had to defend his use of White House talking points while answering questions about the call in an interview that aired Sunday on CBS’s “60 Minutes.”

When asked if Trump’s conduct on the call was “appropriate,” McCarthy dodged the question and said that Trump “did nothing in this phone call that’s impeachable.”

On Monday, Michael Steele, a former chairman of the Republican National Committee, posted a video on Twitter of a woman trying to use a broom to push crashing waves back into the ocean, describing the futile effort as the GOP’s “new strategy to address the #WhistleblowerComplaint.”

Republicans are having a difficult time defending the president because the White House summary of Trump’s call with Zelensky, released last week, is so damning, said Lanny Davis, who helped Clinton navigate the impeachment process as a media surrogate.

According to the summary, Trump told Zelensky to do him a “favor” by working with Barr to investigate various allegations, including unsubstantiated claims of corruption by Biden.

“The statement speaks for itself,” said Davis, a lawyer who now specializes in crisis management. “There’s no way to spin it. You can’t spin the sentence, ‘Do me a favor.’ ”

Carol Morello contributed to this report.