Deep-seated anger — from wives, golden doodles, law professors, the first lady and maybe even George Washington’s hair — was the predominant theme of Wednesday’s House Judiciary Committee hearing, a day-long constitutional cram session on impeachment that ignited a few big fireworks.

(That powdered wig, constitutional scholar Jonathan Turley testified, would catch fire if the nation’s first president and preeminent Founding Father heard the Democrats’ case for removing Donald Trump from office, considering Washington’s exercise of “extreme executive privilege claims.”)

Amid all the accusations and gut-level vitriol on display, outside the House hearing room another impeachment dynamic was beginning to take shape: the self-inflicted 2020 blowback Democrats face for basing their impeachment campaign on President Trump’s attempts to push another country’s leader to investigate Joe and Hunter Biden, their highly questionable dual roles in Ukraine and the obvious conflicts of interest they posed.

On Thursday the former vice president showed just how sensitive he is on the topic. Biden lashed out at an Iowa voter who accused the 77-year-old Democratic primary contender of being too old and helping his son Hunter attain a lucrative role serving on the board of Burisma, a Ukrainian natural gas company, despite having no prior experience in the energy sector.

“You’re a damn liar, man. That’s not true, and no one has ever said that,” Biden fired back. He then challenged the 83-year-old man to a push-ups contest or an “IQ test,” referring to him as “Jack,” in the process.

The video of the ugly exchange immediately went viral, leading even liberal media commentators to press Biden to find a better answer to voters’ legitimate questions about his son’s Burisma role.

If Biden thought that townhall question was tough, he can expect far worse from Senate Republicans as the impeachment enters the next phase and moves to the upper chamber early next year.

Eric Ueland, the White House director of legislative affairs, told reporters Wednesday afternoon that the White House plans to mount an aggressive defense during the Senate trial. The strategy includes spotlighting live witness testimony on the Senate floor – not the videotaped depositions that were submitted as evidence in the Bill Clinton impeachment trial 20 years ago.

Just as the Democrats did over the last several weeks in the House, Republicans in the Senate majority will have a chance to call their witnesses and dominate the process -- with condemnations of those who duck their subpoenas. Topping their list are the former vice president, his son, and Alexandra Chalupa, a former Democratic National Committee operative whom Republicans have accused of digging dirt on the 2016 Trump campaign with help from Ukrainian officials.

Chalupa has said she’s “on a mission” to testify and repudiate such accusations. But there’s a reason Democrats didn’t put her in the hearing hot seat last month. She has publicly said that officials at the Ukrainian Embassy were “helpful” to her efforts to research the activities of Trump campaign chairman Paul Manafort’s Russia ties – even as she insisted the embassy was not trying to interfere in American politics.

Any nuanced distinction without a dramatic difference about Chalupa’s role will likely be lost on many Americans who lived through the nearly two-year-long Mueller investigation, which ended without finding sufficient evidence of Trump campaign collusion with Russia to influence the election.

Joe Biden on Wednesday said he would not testify in impeachment proceedings against President Trump as Republicans focus on the underlying cause for Trump’s concerns about the Bidens’ activities in Ukraine – primarily that Hunter Biden was paid millions to sit Burisma's board while his father served as the Obama administration’s point man on Ukraine. Trump’s efforts to persuade that country’s new president to investigate the matter is at the heart of the impeachment proceedings.

“No, I’m not going to let them take their eye off the ball,” Biden told reporters on the campaign trail when asked if he would acquiesce to Republicans’ calls for him to testify in an impeachment trial. “The president is the one who has committed impeachable crimes. I’m not going to let him diverge from that.”

But even Democratic impeachment witnesses testified last month that Hunter Biden’s role at Burisma raised legitimate conflict-of-interest questions and that they were at a loss to explain why no one in the Obama administration put a stop to it.

Having that unsavory Burisma conflict put into sharp, televised relief during an impeachment trial early next year could be the final jolt that knocks the Biden campaign off its already shaky moorings.

Biden still maintains a 12-point lead in the Democratic contest nationally, but the early primary states are much more of a mixed bag. He’s in fourth place in Iowa and New Hampshire, while remaining solidly in the lead in South Carolina and Nevada, according to RealClearPolitics polling averages.

The timing couldn’t be worse for Biden with the Iowa caucuses coming Feb. 3 and the New Hampshire primary eight days later. Senate Republicans have already signaled they intend to extend an impeachment trial into the primary season.

Before Thanksgiving, Senate Judiciary Committee Chairman Lindsey Graham asked the State Department for documents related to the Bidens and Ukraine, and defended the decision when Biden expressed anger over the move because his onetime colleague “knows me, he knows my son.”

Though Graham has acknowledged the former Delaware senator as a close friend, he said Biden has made mistakes and that friendship would not stand in the way of him doing his job. He said he is specifically focused on the then-vice president boasting about getting a Ukrainian prosecutor fired by threatening to withhold aid to the country. The prosecutor, Viktor Shokin, has said he was investigating Burisma at the time he was fired, but Democrats vehemently dispute that, arguing that he was ousted because he wasn’t pursuing the country’s overall corruption aggressively enough.

“I’m not going to create a country where only Republicans get investigated,” Graham said. “…And we’re going to ask questions of Hunter Biden’s role and getting the prosecutor fired.”

Meanwhile, with Wednesday’s media spotlight focused on the House impeachment hearing, two Republican senators quietly opened a new line of inquiry in their Burisma-centered investigation.

Ron Johnson, who chairs the Homeland Security Committee, and Chuck Grassley, who leads the finance panel, want to know if any Obama administration officials had “actual or apparent” conflicts of interest because of Hunter Biden’s role on Burisma’s board, as well as some of his other international business interests.

Johnson and Grassley sent a letter this week to a Washington-based public relations firm, BlueStar Strategies, that worked for Burisma and interacted with Obama administration officials, including Amos Hochstein, who was serving at the time as a senior adviser to Joe Biden on international energy affairs. In press reports, Hochstein has been described as “a vocal proponent of Ukraine cracking down on Burisma.”

In December 2015, when Joe Biden prepared to return to Ukraine, Hochstein reportedly raised the issue of Hunter Biden’s position on the Burisma board with the vice president but did not recommend that he step down.

George Kent, a State Department official who testified in the impeachment hearings last month, also raised the issue of Hunter Biden’s role on the Burisma board with the Obama White House but was told that the vice president “lacked the further bandwidth to deal with family-related issues at the time” because of his shaky emotional state over the severe illness his other son, Beau, was facing. Beau Biden died of brain cancer in May 2015.