The former president keeps consolidating Republican support, but the legal peril is the greatest he has ever faced and adds to his challenges with independent voters.Donald J. Trump will make his first appearance in federal criminal court on Tuesday. But the former president has been pleading his case for days in a far friendlier venue — the court of Republican public opinion, where he continues to dominate the 2024 field.For Mr. Trump and his team, there has been a sense of familiarity, even normalcy, in the chaos of facing a 37-count indictment in the classified documents case. After two House impeachments, multiple criminal investigations, the jailing of his business’s former accountant, his former fixer and his former campaign manager, and now two criminal indictments, Mr. Trump knows the drill, and so do his supporters.The playbook is well-worn: Play the victim. Blame the “Deep State.” Claim selective prosecution. Punish Republicans who stray for disloyalty. Dominate the news. Ply small donors for cash.His allies see the indictment as a chance to end the primary race before it has even begun in the minds of Republican voters by framing 2024 as an active battle with President Biden. Until now, the main pro-Trump super PAC, MAGA Inc., has focused heavily on Mr. Trump’s chief Republican rival, Gov. Ron DeSantis of Florida, in its $20 million of ad spending. But that messaging has shifted after the indictment, with a new commercial already being shown that pits Mr. Trump directly against Mr. Biden.The intended effect, said a person familiar with the strategy, is to present Mr. Trump as the party’s leader and the presumptive nominee who has already entered a head-to-head battle with Mr. Biden and his Justice Department, making Mr. Trump’s Republican opponents look small by comparison.Mr. Trump, who flew to Florida on Monday ahead of his Tuesday appearance, is determined to serve as narrator of his own high-stakes legal drama. He posted on Truth Social to reveal he had been indicted minutes after his lawyer had called to alert him last week.“The only good thing about it is it’s driven my poll numbers way up,” Mr. Trump told the Georgia Republican Party in a combative speech on Saturday.So far, the indictment fallout appears to be moving along two parallel tracks in different directions, one political, the other legal.Politically, Mr. Trump has continued to consolidate Republican support. In a CBS News poll on Sunday, only 7 percent of likely Republican primary voters initially said the indictment would change their view of Mr. Trump for the worse — and twice as many said it would change their view “for the better.” A full 80 percent of likely Republican voters said Mr. Trump should be able to serve even if convicted.Mr. Trump will make his first appearance in the federal criminal court in Miami on Tuesday.Saul Martinez for The New York TimesLegally, the specificity and initial evidence presented in the charging document that was unsealed on Friday showed the gravity of the case.That evidence includes a recording of Mr. Trump claiming to have a classified document in front of him and acknowledging he no longer had the power to declassify it, photographs of documents strewn across a storage room floor — which Mr. Trump was particularly rankled by — surveillance footage, reams of subpoenaed texts from his own aides and notes from his own lawyer. “If even half of it is true, then he’s toast,” Bill Barr, who served as attorney general under Mr. Trump, said on Fox News. “It’s very, very damning.”As he headed to Miami, Mr. Trump was working to reassemble a legal team shaken by two major resignations on Friday as the special counsel who brought the charges, Jack Smith, said he would push for a “speedy trial.”For Mr. Trump, who has long blurred public-relations woes and legal peril, his 2024 campaign began in part as a shield against prosecution, and victory at the ballot box would amount to the ultimate acquittal. Still, few political strategists in either party see running while under indictment as a way to appeal to the independent voters who are crucial to actually winning the White House.But Mr. Trump has rarely looked past the task immediately in front of him, and for now that is the primary. The CBS poll showed him dominating his closest rival, Mr. DeSantis, 61 percent to 23 percent.“The only good thing about it is it’s driven my poll numbers way up,” Mr. Trump told the Georgia Republican Party on Saturday.Jon Cherry for The New York TimesOn Sunday night, the chief executive of the MAGA Inc. super PAC, Taylor Budowich, sent a memo of talking points to surrogates that tellingly does not mention Mr. DeSantis at all, only Mr. Biden.Another person familiar with the super PAC’s strategy said that the fundamentals of the political race had not changed even as the indictment has brought Mr. Trump the gravest legal threat he’s ever faced. And the PAC would eventually continue attacking Mr. DeSantis, while also elevating other Republican candidates to shear off some of Mr. DeSantis’s support.The uncomfortable initial posture of Mr. Trump’s rivals was captured in a video released by Mr. DeSantis’s super PAC attacking the “Biden DOJ” for “indicting the former president.” Mr. Trump’s team was delighted to see it, even if the ad cast Mr. DeSantis as the man to clean house inside the federal government. Forcing rivals to rally around Mr. Trump, as they see it, is a reaffirmation of the former president’s place at the head of the G.O.P.Yet on Monday, there was a slight shift in tone from solely denouncing the Justice Department. “Two things can be true,” Nikki Haley, the former United Nations ambassador, said on Fox News, adding if the indictment was accurate “President Trump was incredibly reckless with our national security.” Senator Tim Scott of South Carolina called it a “serious case with serious allegations” during a campaign stop in his home state, according to The Post and Courier.The arc of how Mr. Trump has bent the Republican Party and its voters to his interests is not new. He famously joked that he could shoot someone on Fifth Avenue and not lose support in his 2016 campaign.He survived a succession of scandals as president — including the long-running investigation by a previous special counsel, Robert S. Mueller III, that sent some Trump advisers to prison — that few others could. One reason, his advisers and allies say, is that Republican voters have become inured to the various accusations he has faced, flattening them all into a single example of prosecutorial and Democratic overreach, regardless of the specifics.Jack Smith, the special counsel who charged the former president, said he would push for a “speedy trial.”Kenny Holston/The New York Times“Most people on my side of the aisle believe when it comes to Donald Trump, there are no rules,” Senator Lindsey Graham of South Carolina, one of Mr. Trump’s most ardent Republican defenders, said on ABC News’ “This Week” on Sunday. “And you can do the exact same thing or something similar as a Democrat and nothing happens.”The New York Post captured the sentiment succinctly with a tabloid banner on Monday that read, “What About the Bidens?”One Trump adviser, who spoke on the condition of anonymity to discuss strategy, noted that most politicians would assume a defensive crouch when facing a federal indictment. But not Mr. Trump, who delivered two speeches on Saturday, has posted dozens of times on his social media site and is determined to use the national spotlight to drive a proactive message of his own. “It is Trump 24/7, wall-to-wall — why not use that to your advantage?” the adviser said, referring to the blanket media coverage Mr. Trump has been receiving after his indictment.On Monday evening, Mr. Trump did three straight radio interviews, including one with Americano Media, where the host, Carines Moncada, told Mr. Trump that the charges against him had echoes of “persecution” of conservative leaders in Latin America. “I think maybe one of the reasons they like me, so many people have been so hurt in Colombia, in other countries in Latin America, South America,” Mr. Trump replied.The charges, however, could pose a long-term political challenge. An ABC/Ipsos poll from the weekend found that more independents thought Mr. Trump should be charged than thought he should not. And 61 percent of Americans found the charges either very or somewhat serious.In the CBS poll, 69 percent of independent voters said they would consider Mr. Trump’s possession of documents about nuclear systems or military plans a national security risk (46 percent of Republicans said the same, suggesting a potential fracture in the party over that point).On Tuesday, Mr. Trump will fly to New Jersey after his hearing, commandeering the cameras again to deliver prime-time remarks that his team hopes will be televised.Mr. Trump’s advisers took note that some cable and broadcast networks gave live coverage on Monday to the departure of his motorcade as it headed for the airport. On Twitter, the Trump adviser Jason Miller noted that even Fox News, which has generally shied away from extensive live Trump coverage, broadcast footage the motorcade. Mr. Miller had mocked Fox News over the weekend for not carrying Mr. Trump’s appearances live.The Trump operation said it had raised $4 million in the first 24 hours after his previous indictment by the Manhattan district attorney in March. But the campaign has yet to disclose the sum this time.Trump supporters outside Mar-a-Lago on Sunday. Saul Martinez for The New York TimesIn a major fund-raiser that was in the works before the indictment, Mr. Trump is gathering top donors on Tuesday evening at Bedminster, his private club. Those who raise at least $100,000 are invited to attend a “candlelight dinner” after his address to the media.The indictment news has blotted out other developments on the campaign trail. The announcement over the weekend by Mr. DeSantis of his first endorsement from a fellow governor, Kevin Stitt of Oklahoma, was barely a blip. And when Mr. Trump turns himself in at a Miami courthouse on Tuesday, it will keep the attention on the former president.Roughly 15 different groups are trying to galvanize Trump supporters to come to the Miami courthouse for his hearing, according to one person briefed on the plans. The juxtaposition in Mr. Trump’s own language about the stakes, legally and politically, can be jarring.“This is the final battle,” Mr. Trump said on Saturday.But aware of the violence that broke out on Jan. 6, 2021, when Mr. Trump urged supporters to march on the Capitol, he was more cautious on Sunday when speaking to Roger J. Stone Jr., his longest-serving adviser, in an interview for Mr. Stone’s radio show.Mr. Trump said they should join that final battle while protesting “peacefully.” More