Donald Trump, whose single turbulent term in the White House transformed the Republican Party, tested the resilience of democratic institutions in the U.S. and threatened alliances abroad, will lead the GOP in a third consecutive presidential election after clinching the nomination Tuesday.With wins in Georgia, Mississippi and Washington state, Trump surpassed the 1,215-delegate threshold needed to become the presumptive Republican nominee. He'll formally accept the nomination at the Republican National Convention in July, by which point he could be in the remarkable position of being both a presidential candidate and convicted felon. Trump has been indicted in four separate criminal investigations and his first trial, which centers on payments made to a porn actress, is set to begin March 25 in New York City.Trump's victory in the GOP primary ushers in what will almost certainly be an extraordinarily negative general election campaign that will tug at the nation's already searing political and cultural divides. He'll face President Joe Biden in the fall, pitting two deeply unpopular figures against each other in a rematch of the 2020 campaign that few voters say they want to experience again.Thirty-eight percent of Americans viewed Trump very or somewhat favorably in a February poll conducted by the AP-NORC Center for Public Affairs, compared to 41% for Biden.Trump is attempting to return to the White House after threatening democratic norms in the U.S. He refused to accept his loss to Biden in 2020, spending months grasping at baseless conspiracy theories of election fraud that were roundly rejected by the courts and his own attorney general. His rage during a rally on Jan. 6, 2021, helped rile up a mob of supporters who later violently attacked the U.S. Capitol in an effort to disrupt the congressional certification of Biden's win.Only in the wake of the insurrection, with storefronts in the nation's capital boarded up and military vehicles parked on streets to prevent further violence, did Trump accept the reality that Biden would become president. He has since called Jan. 6 “a beautiful day” and aligned himself with those have been imprisoned for their actions — many for assaulting police officers — labeling them “hostages” and demanding their release.Trump has been ambivalent about other basic democratic ideals during his 2024 campaign. He has not committed to accepting the results of this year's election and, during a December interview on Fox News, suggested he would be a dictator for the first day of a new administration. He has aligned himself with autocratic leaders of other countries, most notably Russia's Vladimir Putin and Hungary's Viktor Orbán.Such alliances are a departure from the longstanding posture of the U.S., which has focused on strengthening democracies abroad. But a Trump election could upend U.S. support for Ukraine after its invasion by Russia. And it could have dramatic implications for NATO.Video below: Poll finds GOP voters want a candidate who follows election laws, but still support TrumpDuring his years in the White House, Trump often derided the transatlantic alliance as antiquated and lamented that some countries weren't spending enough on their own defense. He has maintained that critique this year, causing a stir on both sides of the Atlantic in February when he told a rally crowd that he once warned members that he would not only refuse to defend countries that were “delinquent," but that he “would encourage” Russia “to do whatever the hell they want” to them.Legal troubleTrump becomes the GOP's standard-bearer at a time of profound legal trouble, raising the personal stakes of an election that could determine whether he faces the prospect of time behind bars. He faces 91 felony charges in cases that span from the New York hush money case to his efforts to overturn the election and his hoarding of classified documents.While the New York case is moving forward this month, there's significant uncertainty about the trajectory of the other, more serious cases, raising the prospect that they may not be decided until after the election.The Republican Party’s rules for its convention do not address what might happen if the presumptive nominee is convicted of a crime. A conviction wouldn't bar Trump from continuing to run, though a felon has never been a major party nominee or won the White House.If he were to win in November, Trump could appoint an attorney general who would dismiss the federal charges he faces, a remarkable possibility that would undermine the Justice Department's traditional independence from the White House.In addition to the criminal cases, Trump owes in excess of $500 million in fines and interest after a judge in New York ruled he had engaged in a scheme to inflate his net worth to obtain favorable financing. He was ordered to pay $355 million, plus interest, in that case — adding to the $88.3 million he already owed writer E. Jean Carroll after he was found liable of defamation and sexual abuse.Video below: Trump ordered to pay over $83 million to E. Jean Carroll in civil defamation trialTrump, so far, has deftly used the legal cases as a rallying cry, portraying them as a plot hatched by Democrats to keep him out of power. That argument proved powerful among GOP primary voters, with whom Trump remains a deeply popular figure.He now enters the general election phase of the campaign in a competitive position, with voters frustrated by the current state of the economy after years of sharp inflation, despite robust growth and low unemployment, as well as growing concern about the influx of migrants across the southern border. As he did with success in 2016, Trump is seizing on immigration this year, deploying increasingly heated and inflammatory rhetoric in ways that often animate his supporters.The 77-year-old Trump is aided by Biden's perceived weaknesses. The 81-year-old president is broadly unpopular, with deep reservations among voters in both parties about his age and ability to assume the presidency for another four years, though he is not much older than Trump.Biden is also struggling to replicate the coalition that ushered him into the presidency four years ago as some in his party, particularly younger voters and those on the left, have condemned his handling of Israel's war against Hamas.Trump's headwindsWhile those dynamics may play in Trump's favor, he faces stiff headwinds in winning support beyond his base. A notable chunk of GOP primary voters backed his rivals, including Nikki Haley, who ended her campaign after the Super Tuesday races but has not endorsed Trump. Many of those voters have expressed ambivalence about backing him. He'll have to change that if he wants to win the states that will likely decide the election, such as Arizona, Nevada, Georgia, Pennsylvania, Michigan and Wisconsin — each of which he lost in 2020.It remains unclear how Trump’s legal cases will resonate in the general election, particularly among suburban voters, women and independents. Trump's role in appointing the justices who overturned the constitutional right to an abortion could prove a liability in swing states, where women and independent voters are especially influential. He's also made a string of racist comments, including an assertion that his criminal indictments boosted his support among Black Americans, that aren't likely to win over more moderate voters.Still, Trump’s speedy path to the nomination reflects more than a year of quiet work by his team to encourage states to adopt favorable delegate-selection rules, including pushing for winner-take-all contests that prevent second-place finishers from amassing delegates.That helped Trump become the presumptive nominee much earlier than in recent presidential elections. Biden didn't win enough delegates to formally become his party's leader until June 2020. During his 2016 bid, Trump won the needed delegates by May.This year, Trump handily dispatched his Republican primary rivals, sweeping the early voting states that typically set the tone for the campaign. The field included a range of prominent Republicans such as Florida Gov. Ron DeSantis, Haley, his former U.N. ambassador, South Carolina Sen. Tim Scott, former New Jersey Gov. Chris Christie and Mike Pence, who was Trump's vice president.At one point, DeSantis was ahead of Trump in early state polls. But he wilted in the national spotlight, failing to live up to sky-high expectations, despite $168 million in campaign and outside spending. DeSantis dropped out of the race after losing Iowa — a state he had staked his campaign on — and endorsed Trump.In the end, Haley was Trump's last challenger. She only won the District of Columbia and Vermont before ending her campaign. —Associated Press writer Michelle L. Price contributed to this report.