(CNN) On the defensive after President Donald Trump said he would accept assistance from foreign governments in the 2020 election, senior Republicans in Congress pivoted on Thursday and accused Democrats of soliciting foreign help in 2016 because of the infamous Steele dossier.

Here's a breakdown of their claims, the truth about the dossier, and everything in between.

What did Graham say?

Sen. Lindsey Graham, the Republican chairman of the Senate Judiciary Committee, said Trump's campaign should have called the FBI when they were offered dirt from the Russians in 2016. But he also turned his fire to the Democrats, whom he accused of doing the same thing.

"We had a major American political party hire a foreign national, Christopher Steele, to dig up dirt on an American presidential candidate," he said. "As if that was not bad enough, the foreign national compiled an unverified dossier that was then used by the FBI to obtain a warrant against an American citizen and surveil an American presidential campaign."

What did McCarthy say?

House Minority Leader Kevin McCarthy, the top Republican in the lower chamber, said he opposed any foreign interference in US elections but blasted the Democrats in the same breath.

"I watched in the last campaign, the Democratic presidential campaign send $6 million to a foreign entity to travel the world and find something," McCarthy said. "When they could not find something, they made false accusations, salacious accusations at that, drove this country into a special counsel lasting more than 22 months, using this false information, sending it to the FBI and went to get a FISA court then to spy upon Americans."

What is the Steele dossier?

The dossier is a series of memos by retired British spy Christopher Steele. Some of his claims have been debunked, others have held up over time; some remain unproven, and other parts are partially true. (The Mueller report does not support the main claim in the dossier , that the Trump campaign engaged in a widespread conspiracy of collusion with the Russians.)

Additionally, much of what McCarthy said about the dossier is wrong. Democratic nominee Hillary Clinton's campaign indirectly paid for the dossier through a US law firm, which then hired an American opposition research company, which in turn hired Steele. Also, the special counsel investigation was triggered by Trump's firing of FBI Director James Comey, not the dossier.

How was it used by the FBI?

There were also claims in the dossier about Trump campaign adviser Carter Page and his Russian ties. The FBI used some of that information as evidence to support an application to the FISA court, seeking to monitor Page. That FISA warrant was granted in October 2016 by a federal judge.

All of this happened after Page left the Trump campaign amid scrutiny of his Russian ties.

Why is Trump wrong?

Trump has relied on brazen lies and falsehoods while responding to the Russia investigation. In this case, senior Republicans are twisting the facts when they accuse the FBI of using "unverified" and "false information" from the dossier to "spy" on the Trump campaign.

First, some of the information from Steele was included in the FISA application and has been partially corroborated, according to the Mueller report and Congressional testimony.

Second, investigators used more than just the dossier to get the FISA warrant. They mentioned Page's past ties to known Russian spies in New York, and other materials that are still redacted.

Third, this discussion only revolves around the first of four FISAs against Page. Investigators went back to the court repeatedly, with new information, and demonstrated that they were collecting valuable information. All four FISA applications were granted by federal judges.

What did the dossier say?

Page visited Russia in July 2016, while still advising the Trump campaign. He delivered a public address at a prominent Moscow university and met with Russian government officials.

The dossier said Page had a secret meeting with Igor Sechin, the president of Rosneft, a state-run oil company. Steele claimed that they discussed a potential deal for Trump to lift US sanctions in exchange for future energy cooperation between the two countries. Part of the alleged quid-pro-quo would have included the planned sale of a 19% stake in Rosneft.

Steele also claimed that Page met with another Kremlin official, Igor Divyekin, who raised the prospect of political "kompromat" with Page, dirt they allegedly had on both Clinton and Trump.

The FISA application, parts of which were declassified last year, cited the alleged meeting with Sechin, the discussion of sanctions, the alleged meeting with Divyekin, and the discussion of "kompromat." The information was attributed to "Source #1," a reference to Steele, and the application disclosed that Steele was hired as part of an effort to discredit Trump's campaign.

What was corroborated?

No public evidence has emerged to support the allegation that Page colluded with the Russian government or was sent to Russia by the Trump campaign to coordinate on the election.

There is no proof Page met with Sechin, and Page has denied it.

But under questioning by the House Intelligence Committee, Page admitted that he met a different Rosneft official during the trip: Andrey Baranov, Rosneft's head of investor relations. He said he didn't recall any conversation about sanctions. But the Mueller report said they did talk about the planned sale of a stake in Rosneft, which was mentioned in the dossier.

Page denied ever meeting Divyekin, and there's no proof that Page discussed "kompromat" with anyone in Russia. But during his closed-door congressional testimony, Page acknowledged that he also had a conversation with Arkady Dvorkovich, a deputy Prime Minister.

Some of the details in the dossier were wrong. But Steele was right that Page attended high-level meetings with Russians during his trip, even though Page was denying it at the time.

What about the Mueller report?

Seven pages of the Mueller report are specifically devoted to Page's connections to Russia.

"Russian intelligence officials had formed relationships with Page in 2008 and 2013 and Russian officials may have focused on Page in 2016 because of his affiliation with the Campaign," the report said. "However, the investigation did not establish that Page coordinated with the Russian government in its efforts to interfere with the 2016 presidential election."

The Mueller report also cited Page's history with Russian spies in Manhattan, referring to much of the same information that federal investigators used in the initial FISA application.

There were still some questions about Page that Mueller couldn't answer.

"The Office was unable to obtain additional evidence or testimony about who Page may have met or communicated with in Moscow; thus, Page's activities in Russia-as described in his emails with the Campaign-were not fully explained," the report said.