Impeachment is getting a jump-start.

Sure, some intervention — divine, political or otherwise — could still stop the House from voting on the political equivalent of an indictment on crimes against the nation.

But House Democrats have been pulling together a wide-ranging case to impeach President Donald Trump on a series of alleged past and ongoing crimes against the country — a set of charges that goes far beyond the Mueller report — and all signs point to a possible public inflection point later this week, when acting Director of National Intelligence Joseph Maguire testifies before the House Intelligence Committee.

"The dam could break on Thursday," said one senior House Democratic aide, whose boss has not endorsed impeachment.

The panel's chairman, Rep. Adam Schiff, D-Calif., has been the most reluctant of Speaker Nancy Pelosi's top lieutenants to move toward impeaching the president, but Democrats say Schiff is spitting hot vinegar over Maguire's decision, at the insistence of the Justice Department, to withhold an intelligence community whistleblower's complaint about Trump's dealings with Ukraine.

Rep. David Cicilline, D-R.I., said Democrats should move forward quickly with impeachment if Maguire doesn't turn over the complaint.

"That’s independent grounds to file articles of impeachment," he said in a telephone interview with NBC News Monday. "That relates to this ongoing obstruction and stonewalling."

Cicilline and other Democrats say it appears that Trump abused his power to help himself politically.

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Over the summer, as he held back congressionally approved U.S. aid to Ukraine, Trump spoke with that country's new president, Volodymyr Zelensky, about former Vice President Joe Biden's son Hunter, whom Trump has accused, without evidence, of benefiting from corruption in Ukraine.

Trump has acknowledged that much. He appears to relish bringing Biden's name into the mix, as he has spoken about the controversy repeatedly and publicly while trying to gain political advantage over the elder Biden, the front-runner for the Democratic presidential nomination. So has his personal lawyer, Rudy Giuliani, who has been an emissary to Ukraine on the matter.

The Wall Street Journal reported that Trump repeatedly asked Zelensky in a July phone call to open an investigation into Hunter Biden — also saying, citing the same source, that Trump did not offer a quid pro quo in the conversation.

If it is shown that Trump held back aid to force Ukraine to go after the younger Biden, impeachment "may be the only remedy," Schiff told CNN on Sunday.

Democrats contend that the Trump administration is illegally obstructing Congress' work by blocking Schiff from access to the whistleblower complaint — which, if it didn't involve the president, would normally be shared with the chairman of the committee. If Maguire doesn't turn it over, House Speaker Nancy Pelosi, D-Calif., told her colleagues in a letter over the weekend, the impeachment investigation will enter a "whole new stage."

Trump has said he may be willing to release a transcript of his call, but Democrats are insistent that they want the complaint, which could include more information than the substance of the discussion between the two leaders, and which is what Democrats believe Schiff is entitled to see under the law.

If anything, Pelosi is still holding back the public edge of a process that has been moving apace behind closed doors. Her staff was scheduled to meet Monday, as it does every week, with aides to the six committees currently involved in investigating the president.

The scope of the impeachment charges under consideration by Democrats is breathtaking, according to those familiar with the discussions.

Russian interference in the 2016 election — and the Trump family's efforts to hide its dealings with Moscow — has become a shrinking piece of the impeachment puzzle as Trump has taken ever-bolder actions to frustrate the basic oversight work of Congress in its investigation into that matter and others involving the president.

Democrats are also gathering evidence for possible obstruction of justice charges stemming from special counsel Robert Mueller's investigation — including the eyewitness testimony the Judiciary Committee received from former Trump campaign manager Corey Lewandowski last week. Lewandowski testified that the president twice directed him to tell then-Attorney General Jeff Sessions to un-recuse himself and shut down Mueller's investigation of Trump.

The other buckets of potentially impeachable offenses include obstruction of Congress, a category that covers a laundry list of efforts by Trump to prevent the House from obtaining testimony and documents from various federal officials, agencies and even people who do not work for the government — like Lewandowski — over whom Trump has sought to limit disclosures by asserting executive privilege.

Then there are allegations that Trump has used his office to enrich himself in violation of the Constitution's "emoluments" clause, which prohibits federal officeholders from benefiting financially from their positions.

Democrats say the president's interactions with Ukraine's leader, and the administration's push to conceal them from Congress, have created another pot of potentially impeachable offenses that overlap with existing abuse-of-power and obstruction allegations.

And finally, there's a miscellaneous category that involves such headings as the president's alleged failure to defend the country from enemies and his re-appropriation of congressionally approved funds to build a border wall.

It's unlikely that all of those counts would end up in articles of impeachment — only the strongest would survive — and they could be sliced and diced in any number of permutations to arrive at only a handful of actual charges. But the universe of possibilities is large and it has expanded considerably in just the last couple of weeks, as the president has chosen to fight congressional investigators rather than cooperate with them.

For Trump, who is unlikely to be removed from office by the Senate under any circumstances, the main war is about what impeachment means for his re-election chances.

He and his allies are pursuing a narrative that Biden used his influence as vice president to shut down an investigation into a company that his son worked for — and that Hunter Biden improperly received millions of dollars — even though that probe apparently was no longer active at the time.

In an op-ed in The Washington Post, lawyers George Conway and Neal Katyal argued that the Ukraine affair is more demanding of Trump's impeachment than the evidence from the Russia probe.

"The current whistleblowing allegations, however, are even worse," they wrote. "Unlike the allegations of conspiracy with Russia before the 2016 election, these concern Trump’s actions as president, not as a private citizen, and his exercise of presidential powers over foreign policy with Ukraine."

They continued, "Moreover, with Russia, at least there was an attempt to get the facts through the Mueller investigation; here the White House is trying to shut down the entire inquiry from the start — depriving not just the American people, but even congressional intelligence committees, of necessary information."

For House Democrats, the question of impeachment has suddenly become more pressing.

Said an aide to a lawmaker who has long favored moving forward on impeachment: "If this isn’t the moment, then what is?"