Cedar Rapids, Iowa(CNN) The FBI's decision to review new emails related to Hillary Clinton's use of a private email server is reinvigorating Donald Trump's faith in the US government and political system -- and in his own campaign.
"What happened today, starting with the FBI, maybe the system will become a little less rigged. Beautiful," the Republican nominee, who has repeatedly questioned what he deems a "rigged system" against him, said Friday night. It was the third and final rally of a day he argued has breathed new life into his struggling campaign.
He argued his campaign is "really moving" in light of what he termed a "disaster" for Clinton's campaign and then the billionaire showman even capped off the outdoors rally on a riverbank here with a flashy fireworks display.
"The FBI would not have reopened this case at this time unless it were a most egregious offense," Trump argued, even though the FBI has not said it is formally reopening the investigation into Clinton's email server. "I've had a lot of words about the FBI lately, but I give them great credit for having the courage to right this horrible wrong."
Pivoting back to his campaign, he added: "We've had gaps, but we are really moving. I don't know what's going to happen now."
Earlier in the day, FBI Director James Comey announced in a letter to members of Congress that through "an unrelated case, the FBI has learned of the existence of emails that appear pertinent to the investigation" of Clinton's email server. Comey directed investigators to "review these emails to determine whether they contained classified information."
The decision, which fell nearly four months after the FBI recommended no criminal charges following its investigation into Clinton's private email server, rocked the political world on Friday. It came just 11 days before Election Day as Trump faces a steep and narrow path to victory following a series of damaging revelations in recent weeks -- including sexual assault allegations and audio of Trump bragging about being able to grope women.
If the fireworks shed light on Trump's mood, his supporters' ear-shattering shrieks, applause and chants of "Lock her up!" at each of his three rallies when Trump raised the "critical breaking news" left no doubt the FBI's surprise decision had reinvigorated his biggest fans.
First pouncing on the news at a rally in Manchester, New Hampshire, Trump first expressed hope that the FBI will "right the horrible mistake that they made" and lambasted Clinton as a corrupt candidate, even though no new evidence came to light on Friday.
"Hillary Clinton's corruption is on a scale we have never seen before. We must never let her take her criminal scheme into the Oval Office," Trump said, reading from prepared remarks. "I have great respect for the fact that the FBI and the Department of Justice are now willing to have the courage to right the horrible mistake that they made."
Clinton reacted to the FBI announcement during a brief news conference Friday afternoon, urging the FBI to release "full and complete facts immediately."
"The director himself has said he doesn't know whether the emails referenced in his letter are significant or not. I'm confident, whatever they are, will not change the conclusion reached in July. Therefore, it's imperative that the bureau explain this issue in question, whatever it is, without any delay," Clinton said.
A few hours later, Trump lobbed another attack at Clinton during a rally in Cedar Rapids, Iowa, accusing Clinton of trying to "politicize this investigation" and of "attacking and falsely accusing the FBI director," noting that Clinton claimed Comey sent a letter only to Republican members of Congress. The FBI director also sent the letter to top Democrats as well.
"The FBI would not have reopened this case at this time unless it were a most egregious offense," Trump argued in Cedar Rapids.
Trump's accusation that Clinton is trying to "politicize" the investigation and attacking the FBI director sits in stark contrast to Trump's own repeated and unrelenting attacks on the agency.
Trump has repeatedly accused the FBI and DOJ of colluding to cover up Clinton's controversial use of a private email server during her time as secretary of state.
And while he made it clear Friday that he was not backing off that claim, Trump appeared cautiously optimistic that the FBI's latest announcement might finally yield the result he and his supporters have been clamoring for. Trump has argued Clinton should be jailed for storing several pieces of classified information on her private email server and misrepresenting that fact to the American public, though he did not explicitly say Friday that Clinton should be indicted or jailed.
"This was a grave miscarriage of justice that the American people fully understood and it is everybody's hope that it is about to be corrected," Trump said.
Minutes later, he added: "It might not be as rigged as I thought."
"The FBI, I think they're going to right the ship, folks, I think they're going to right the ship and they're going to save their great reputation by doing so," Trump said.
While Trump remained stern-faced as he addressed the FBI's decision to investigate new emails related to Clinton's email server, Trump's supporters and his campaign staff were suddenly reinvigorated by the news.
Trump's campaign manager, Kellyanne Conway, was being interviewed by Yahoo News' Bianna Golodryga when the news first broke.
"That is superb," Conway said after Golodryga told her. "That is extraordinary news for the American people because they deserve to know everything."
She later tweeted: "A great day in our campaign just got even better."
Trump's reaction to the FBI news echoed the response of other top Republican officials, including House Speaker Paul Ryan -- who has been critical of Trump but still supports him for president.
Ryan called the FBI's decision "long overdue" and hammered Clinton for her "reckless use of a private email server, and her refusal to be forthcoming with federal investigators."
"Hillary Clinton has nobody but herself to blame. She was entrusted with some of our nation's most important secrets, and she betrayed that trust by carelessly mishandling classified information," Ryan said in a statement Friday.
Republican National Committee Chairman Reince Priebus called the news a "stunning development" and argued Clinton "jeopardized classified information."
Priebus also suggested the FBI's announcement raised questions about the 33,000 emails Clinton deleted from her private email server, which Trump has frequently raised on the stump.
"This stunning development raises serious questions about what records may not have been turned over and why, and whether they show intent to violate the law," Priebus said.