Donald Trump has launched a blistering attack on “election interference at a scale never seen before” in the US, casting himself as a victim of political persecution after he became the first former president to face criminal charges.

In a grievance-filled speech on Tuesday night from the ballroom at his Mar-a-Lago estate in Florida, Trump lashed out not just at Alvin Bragg, the Manhattan district attorney who has brought the case, but also at prosecutors investigating him across the country from Georgia to Washington.

Trump’s appearance capped a day of drama that started in New York when he was arraigned in a Manhattan courthouse and pleaded not guilty to 34 counts of falsifying business records.

“The only crime I have committed is to fearlessly defend our nation from those who seek to destroy it,” he said.

Trump seemed emboldened by the sceptical reaction to the charges brought by Bragg from Republicans who have been critical of the former president and leery of his chances of recapturing the White House for the party in 2024. Mitt Romney and John Bolton — persistent critics of the former president — lashed out at the case, describing it as politically motivated and short on substance.

“I believe President Trump’s character and conduct make him unfit for office,” said Romney, the Utah senator. “Even so, I believe the New York prosecutor has stretched to reach felony criminal charges in order to fit a political agenda.”

Bolton said of the indictment, which was unsealed on Tuesday afternoon: “Speaking as someone who very strongly does not want Donald Trump to get the Republican presidential nomination, I’m extraordinarily distressed by this document.”

“I think this is even weaker than I feared it would be,” added Bolton, who previously served as Trump’s national security adviser before he was ousted.

Many Democrats were wary of cheering on Trump’s prosecution. “I believe that Mr Trump will have a fair trial that follows the facts and the law,” said Chuck Schumer, the Senate majority leader.

The judge presiding over the case in New York urged the former president to refrain from making comments that would “incite violence, create civil unrest, or jeopardise the safety or wellbeing of any individuals”.

However, Trump pulled few punches in his Mar-a-Lago speech, claiming that he would not receive a fair trial because of a “Trump-hating judge with a Trump-hating wife and family”. He also lambasted the special prosecutor investigating his role in the January 6 riots and handling of classified documents, describing him as a “lunatic”.

Fani Willis, a black local prosecutor in Georgia investigating his alleged attempts to overturn the 2020 election result, was a “racist”, he added.

Some Democratic pundits suggested the vitriolic tone of speech could backfire. “I sort of agree that, in the short term, today’s indictment could help Trump politically. But this speech gives me pause,” David Axelrod, Barack Obama’s former political strategist, wrote on Twitter. “Does even his base want to hear this for the next two years or six?”

Earlier, Bragg accused Trump of masterminding an expansive scheme to suppress damaging stories that might have threatened his successful 2016 campaign.

This included arranging a $130,000 payment to Stormy Daniels, an adult film actress, made 12 days before Trump took office, in order to bury a story about their alleged affair, Bragg’s office said.

Payments totalling $180,000 were also made to another woman alleging an affair — believed to be Playboy model Karen McDougal — as well as a former doorman at Trump Tower, according to a statement of facts provided by Bragg’s office.

However, the 16-page indictment was far narrower in scope, outlining alleged crimes linked to the recording of payments made in 2017 to reimburse Trump’s erstwhile lawyer Michael Cohen, who originally made the payment to Daniels using his own money.

Bragg told reporters: “At its core, this case today is one with allegations like so many of our white collar cases, allegations that someone lied again and again to protect their interests and evade the laws, to which we are all held accountable.”

He added that his office would “uphold our solemn responsibility to ensure that everyone stands equal before the law: no amount of money and no amount of power changes that enduring American principle”.

Trump launched a fundraising effort following the indictment. His senior adviser Jason Miller claimed the former president has raised more than $8mn in the four days since a New York grand jury voted to indict him.