In October 1984, Senator Joseph R. Biden Jr. of Delaware was invited to address a conservative Baptist church near Wilmington as he campaigned for a third term.
Mr. Biden, hardly the favorite of social conservatives, was in hostile political territory. But as the incumbent, he was given the first speaking slot — and he used it to hold court uninterrupted for nearly an hour. Mr. Biden’s Republican opponent barely got to introduce himself before time was up for the event, while the dozens of other candidates there for the forum never got a word in.
The episode, from “Only in Delaware,” a political history of Delaware by Celia Cohen, a longtime Wilmington journalist, illustrates just how easily Mr. Biden was able to sweep challengers to the side — not just in that race, but throughout his Senate career. Incumbency gave him a staggering advantage.
In 30 years, Mr. Biden never encountered a serious threat to his office. His Republican opponents were underfunded, little-known, inexperienced or some combination of the three. None of them took more than 41 percent of the vote against him.
His re-election fight against former President Donald J. Trump — his 13th bid for federal office, all told — is shaping up to be the opposite of those long-ago Senate campaigns: travel-intensive, nasty and close. A rival is, for the first time with him atop the ticket, forcing him to make a compelling case for his return.
Before his 2020 presidential campaign, which in the general election was light on in-person events because of the coronavirus pandemic, Mr. Biden had never had a harshly negative advertisement about his record in office or his character broadcast against him on television, according to the archive of congressional television and radio advertisements at the Carl Albert Congressional Research and Studies Center at the University of Oklahoma. None of his Senate rivals attacked him on TV, and he ended his two prior presidential campaigns before opponents got around to attacking him.
The Republicans who ran against Mr. Biden in Delaware described him as a strong incumbent who was widely liked, and much quicker on his feet during debates and candidate forums than the president they see today. Mr. Biden has ramped up his travel schedule with a flurry of carefully managed visits to battleground states in recent weeks, and the 81-year-old president will be expected to keep up the pace while avoiding the sort of verbal flubs that often dog his public appearances.
Just last week, Mr. Biden prompted the crowd at an endorsement event to chant, “Four more years!” and then added “pause” as it appeared to have been written into his teleprompter, an episode that drew much mocking in conservative news media and quiet forehead-slapping among Democrats.
In Delaware, Mr. Biden was so well known and, in his early years in office, had such a wellspring of sympathy from voters after the tragic crash that killed his first wife and daughter, that no rival ever mounted a sustained case that he should not be re-elected. For years, bumper stickers promoting his re-election just said “Joe,” while opponents lost with an array of long-forgotten slogans.
“I don’t think he ever broke a sweat once he was an incumbent,” said Jane Brady, a Republican who lost to Mr. Biden by 27 points in 1990.
The only negative ad run against Mr. Biden between 1978 and 2008, according to the University of Oklahoma’s archive, is one that his campaign would most likely embrace today. That 30-second spot reminded viewers that President Ronald Reagan endorsed John Burris, Mr. Biden’s Republican challenger in 1984, while Mr. Biden backed the unpopular Democratic presidential nominee, Walter Mondale.
Mr. Biden, the ad stated, opposed Mr. Reagan 58 percent of the time — not exactly in lock step against the Republican president. “You have a choice,” the narrator intoned. “The Reagan-Burris team, the Mondale-Biden team or no team at all.”
Mr. Biden won by 20 points.
Now a 78-year-old retiree, Mr. Burris said it was cost-prohibitive for him to become as well-known to voters as Mr. Biden already was. So he tried to get under Mr. Biden’s skin in order to expose his temper and “create a Bad Joe” that would undercut Mr. Biden’s sympathetic image. In his telling, Mr. Biden did not take the bait.
“Where Trump has absolutely no compunction at going to the basest level he can to try to get a result, I saw Joe moving into that very reluctantly,” Mr. Burris said. “The whole scene now is not emblematic of what he’s used to doing.”
When Mr. Biden first won election to the Senate in 1972, in an year Democrats took sweeping victories in Delaware, he ousted Senator Caleb Boggs, a two-term Republican and former governor who had been in office in Delaware for 30 years. Mr. Biden’s radio ads coyly suggested Mr. Boggs was pro-heroin and said he was stuck in a generation worried about Joseph Stalin. The ads ended with an upbeat slogan — “Joe Biden: He understands what’s happening today.”
Once elected, Mr. Biden and his early opponents sought to abide by the “Delaware Way,” an informal code of politics that mandated a clubby politeness that had the effect of blurring the differences between the two parties. Mr. Biden’s sons and Mr. Burris’s stepson went to school together. For years after the campaign, the two men golfed together, and as vice president Mr. Biden had Mr. Burris and his granddaughter into the White House.
By the 1990s, that dynamic slowly began to change, though Mr. Biden’s Senate opponents still did not have the resources to mount a negative campaign against him. Ms. Brady, in her 1990 campaign, sought to capitalize on the plagiarism scandal that doomed Mr. Biden’s 1988 presidential run. But without money to amplify the embarrassing story on television, Ms. Brady’s campaign spliced together 11 minutes of network news footage recounting the story on 40,000 VHS tapes and mailed them to addresses on the Delaware voter rolls.
The episode drew howls of protests from the Biden campaign and the news networks. NBC filed a formal protest claiming copyright infringement. But few people actually saw the spliced footage. Ms. Brady’s campaign had a voter list filled with outdated addresses, and she said campaign volunteers wound up fishing VHS tapes out of dumpsters at the Wilmington post office so that they could hand them out at parades and other local campaign stops.
“I wasn’t raising a lot of money, and nobody thought I could win,” Ms. Brady said. “It was a very harsh experience.”
Mr. Biden’s opponent in 1996 and 2002 was Ray Clatworthy, an entrepreneur who owned restaurants and local Christian radio stations. During a 1996 televised debate, Mr. Clatworthy accused Mr. Biden of raising taxes while voting to increase his own salary and accused him of “attempting to portray himself as a conservative” in an election year.
Mr. Biden spoke quickly and precisely, without entering the verbal cul-de-sacs endemic to many of his presidential speeches 28 years later.
Mr. Biden sought to pin down Mr. Clatworthy on his anti-abortion stance and then delivered a clear statement of his own views on the issue after Mr. Clatworthy accused him of flip-flopping to endorse abortion rights in his 1988 presidential campaign.
“My position has been consistent from the very beginning,” Mr. Biden said of his abortion stance. “I believe government should stay out — no constitutional amendment, no public funding.”
Mr. Clatworthy and his family were less enamored by Mr. Biden than some of his other former rivals. When Mr. Clatworthy died in 2021, his family described his political career this way in a paid obituary: “As a patriot, he ran for United States Senate in Delaware twice against a gentleman for whose name we are at a loss.”
Mr. Trump, 77, is a rare president to be defeated while seeking a second term and has a host of political vulnerabilities, including the criminal cases and his role in undoing the constitutional right to an abortion. He has spent most of the days since his New York trial began in court, as is required, while Mr. Biden has hit the campaign trail, making stops in battleground states.
Mr. Biden’s 2024 campaign aides said his 2020 victory over Mr. Trump, who spared little expense in attacking him, is sufficient evidence that he can run a successful and modern campaign.
“After defeating over 20 primary candidates, Joe Biden won more votes than any other candidate in our country’s history and became just the third person to defeat an incumbent president in the last century,” said Lauren Hitt, a campaign spokeswoman. “This November, he’ll beat Trump and the naysayers again.”
The last Republican before Mr. Trump to try to oust Mr. Biden from his office was Christine O’Donnell, who by 2008 had already run for the Senate once and would rocket to political fame two years later when she began a TV ad for a subsequent Senate race with the instantly infamous proclamation: “I’m not a witch.”
In a rare interview, Ms. O’Donnell, who moved to Florida to attend law school, ticked through the hurdles her 2008 campaign had faced. She said the Delaware Republican Party opposed her brand of conservative politics. Mr. Biden, off running for vice president, refused to debate her, so she was left to appear opposite his surrogates at candidate forums. She believes some voter fraud cost her votes in the state’s most populous county. (There is no evidence of this.) .
“In 2008, the Republicans were actually campaigning against me. They were working with Joe Biden to undermine my efforts,” she said. “It’s a shame, because, voter fraud aside, people are pretty conservative in Delaware. You could turn that state red with free and fair elections.”
Ms. O’Donnell said she planned to present her evidence for this in an eight-part podcast that she expects to release this summer.
Kitty Bennett contributed research.