WASHINGTON (AP) — Three leading legal scholars testified Wednesday that President Donald Trump’s attempts to have Ukraine investigate Democratic rivals are grounds for impeachment, bolstering the Democrats’ case as House Speaker Nancy Pelosi made sure they’re prepared for that momentous next step.

Meeting behind closed doors ahead of an initial Judiciary Committee hearing to consider potential articles of impeachment, Pelosi asked House Democrats a simple question: “Are you ready?”

The answer was a resounding yes.

Though no date has been set, the Democrats are charging toward a Christmastime vote on removing the 45th president. It’s a starkly partisan undertaking, a situation Pelosi hoped to avoid but now seems inevitable.

Trump is alleged to have abused the power of his office by putting personal political gain over national security interests, engaging in bribery by withholding $400 in military aid Congress had approved for Ukraine; and then obstructing Congress by stonewalling the investigation.

Across the Capitol on Wednesday, the polarizing political divide over impeachment, only the fourth such inquiry in the nation’s history, was on display.

At the Judiciary hearing Democrats sided with the scholars who said Trump’s actions reached the Constitution’s threshold of “bribery or other high crimes and misdemeanors.” Republicans pointed to the lone professor they were allowed to invite, who said impeachment was not warranted.

Democrats in the House say the inquiry is a duty. Republican representatives say it’s a sham. And quietly senators of both parties conferred on Wednesday, preparing for an eventual Trump trial.

“Never before, in the history of the republic, have we been forced to consider the conduct of a president who appears to have solicited personal, political favors from a foreign government,” said Rep. Jerrold Nadler, D-N.Y., as he gaveled open the landmark House hearing.

Nadler said Trump’s phone call seeking a “favor” from Ukrainian President Volodymyr Zelenskiy wasn’t the first time he had sought foreign help to influence an American election, noting Russian interference in 2016. He warned against inaction with a new campaign underway.

“We cannot wait for the election,” he said. ” If we do not act to hold him in check, now, President Trump will almost certainly try again to solicit interference in the election for his personal political gain.”

Trump, attending a NATO meeting in London called the hearing a “joke” and doubted many people would watch because it’s “boring.”

Once an outsider to the GOP, Trump now has Republicans’ unwavering support. They joined in his name-calling the Judiciary proceedings a “disgrace” and unfair, the dredging up of unfounded allegations as part of an effort to undo the 2016 election and remove him from office.

“You just don’t like the guy,” said Rep. Doug Collins of Georgia, the top Republican on the panel. Trump rewarded some of his allies with politically valuable presidential tweets as the daylong hearing dragged into the evening.

Despite the intent of America’s Founding Fathers to create a durable system of legal checks and balances, impeachment is an admittedly political exercise. Thus Pelosi asked her still-new majority if they were willing to press onward, aware of still-uncertain electoral risks.

At the Democrats’ private morning meeting, support for the impeachment effort was vigorous, though voting to remove Trump could come hard for some lawmakers in regions where the president has substantial backing.

The Democratic lawmakers also delivered a standing ovation to Rep. Adam Schiff, whose 300-page Intelligence Committee report cataloged potential grounds for impeachment, overwhelmingly indicating they want to continue to press the inquiry rather than slow its advance or call a halt for fear of political costs in next year’s congressional elections.

)The meeting was described by people familiar with it, who were unauthorized to discuss it by name and were granted anonymity.

Meanwhile, Trump’s team fanned out across the Capitol with Vice President Mike Pence meeting with House Republicans and White House officials conferring with Senate Republicans to prepare for what could be the first presidential impeachment trial in a generation.