A long-simmering fight is back on this week over the role of the infamous Donald Trump dossier after a new report that confirmed that the Democratic National Committee and Hillary Clinton's campaign helped fund it.

The battle over the unverified dossier is a crucial front in the broader political fight over the Trump White House, the public's perceptions of the president and his stunning election win.

The DNC and Clinton campaign's role in funding the dossier, which was reported by the Washington Post, doesn't add much to what was already public. It's been understood for months that the research that went into the document was initially underwritten by Trump's Republican opponents during the GOP primary season, and later taken over by Democrats during the general election campaign.

Still, the president and his supporters have seized on the new details about the DNC-Clinton role to push their view that the various Russia investigations — from Capitol Hill to Justice Department special counsel Robert Mueller — are based on a fraudulent, politically inspired hit job.

In short, they argue, if the dossier is the case that Trump's campaign colluded with Russia's attack on the election, that means there's no case.

Citing Fox News, Trump tweeted Wednesday morning, "Clinton campaign & DNC paid for research that led to the anti-Trump Fake News Dossier. The victim here is the President."

He later repeated to reporters on the South Lawn of the White House his sometime theory that the Russia collusion story is a Democratic hoax.

The president's allies have also taken up the message.

Erick Erickson, a conservative blogger and radio host, wrote that "both the DNC campaign apparatus and the Democratic leader, Barack Obama via his FBI, tried to dig up dirt on Trump."

"This should all be kept in mind as the Democrats continue to claim Russia stole the election and that Donald Trump has all sorts of nefarious ties to Russia," he added. "Many of those claims, now, appear to really have been generated in an incestuous relationship of sore losers."

For months, Republicans on the Hill have been trying to discover who specifically was behind the dossier. Its author is known, revealed as the former British intelligence officer Christopher Steele, who compiled the material for an American political investigation firm called Fusion GPS.

Political campaigns routinely pay outfits like Fusion GPS to generate "opposition research" on their adversaries. In this case, the desire to learn more about Trump's connections to Russia began with one of his primary opponents in 2016.

The identity of that campaign hasn't been confirmed, but Trump suggested on Wednesday he might know it.

Later — presumably after the initial Republican sponsor's campaign ended with Trump's victory in a primary — Democrats and Clinton's campaign began paying Fusion GPS to keep up its work, according to the Post. The FBI also is said to have paid Steele, although it cut off its relationship with him after his name became public.

The chairman of the Senate Judiciary Committee, Chuck Grassley, R-Iowa, has pushed the FBI for an explanation about how it used the dossier in its investigation of Russian interference in the 2016 election.

Republicans on the House Intelligence Committee, which is probing Russia's election role, have done so as well.