Within hours of the Australian government announcing a “giveaway” budget that Scott Morrison had hoped would propel him to a second term as prime minister, his own party began tearing into him.

Concetta Fierravanti-Wells, a senator from Morrison’s Liberal party, unleashed a blistering 10-minute character assassination, calling her boss an “autocrat (and) a bully who has no moral compass” who was unfit to be prime minister.

The verbal onslaught was just the latest damaging blow landed on Morrison from his own side ahead of the May 21 election. In the past two months, leaked messages from his colleagues have painted him as a “complete psycho”, “a fraud” and a “hypocrite and a liar”. He has also been accused of racially vilifying a rival candidate a decade ago to win a seat in parliament. Morrison has denied the accusation.

Next month’s poll was set to be fought on important issues ranging from pandemic management, the strength of the economy, climate change and the growing geopolitical tension with China.

But the election is fast turning into a personal ballot on Morrison with his Liberal colleagues providing the opposition Labor party, led by Anthony Albanese, with ample ammunition to dethrone Australia’s longest serving prime minister in 15 years.

Morrison has portrayed himself as an “ordinary bloke” standing up for “quiet Australians”. But analysts said he has alienated sections of his own party with an abrasive style that have led to accusations of bullying, interference, dishonesty and initiatives aimed at press conference bravado but which lack any substance. 

Those sentiments appear to chime with voters. A Roy Morgan poll published last week found the Labor party attracting 57 per cent of the vote in a choice between the two main parties. The opposition leads in all of Australia’s states and is extending its lead in most of them.

Michele Levine, chief executive of Roy Morgan, said that hopes of a “bounce” in the polls on the back of the budget, which was aimed at easing cost-of-living pressures, had been quashed by the infighting within Morrison’s party. “There is an old political axiom that disunity is death,” she said.

Katie Allen, a Liberal MP, warned that there was “no doubt” that Morrison’s unpopularity was a factor in her “blue heartland” seat of Higgins, which has never fallen to Labor.

Catherine Cusack, a long-serving Liberal politician in Morrison’s home state of New South Wales, went further and said she would not vote for Morrison’s re-election because of his “scheming” response to recent floods. “My bullshit tolerance levels are at zero,” she said.

Morrison told national broadcaster ABC that the criticisms from within his own party were from people with “an axe to grind”.

But members of the public are unimpressed, too. His efforts to connect with voters, such as serenading his family with a ukulele, washing a woman’s hair in a salon and soldering without protective eyewear, have foundered.

Mark Kenny, a professor at the Australian National University, said that the personal attacks on Morrison had exposed his vulnerability.

“His strength in 2019 was that people didn’t know him. His weakness in 2022 is that people do,” said Kenny.

Morrison should be entering the election in a robust position. He is the first Australian prime minister to serve a full term since 2007 as four prime ministers — from both big parties — have been toppled midterm. Despite near constant speculation of a challenge to the leadership, he has held on to fight for a second term.

The prime minister can also point to a strong economic recovery since the coronavirus pandemic started and unemployment at only 4 per cent as evidence of his government’s success. The Russian invasion of Ukraine has reinforced Morrison’s focus on Indo-Pacific alliances to counter China and to strengthen military ties with the US and UK. At the same time, he has forged trade agreements with Japan and India.

Yet Kenny said that Morrison had struggled to convince voters of his leadership style. He has been accused of “dithering” during crucial events including the 2019 bushfires, a sexual assault scandal in parliament and the factional tensions in his party that have boiled over ahead of an election. “He’s essentially handcuffed by his own indolence,” Kenny said.

Albanese has outflanked Morrison in the run-up to the election by providing no radical policies for his rival to criticise. Morrison has instead attacked Labor’s lack of substance, which was reinforced on Monday when Albanese could not answer what the interest rate or unemployment levels were when asked by journalists.

Morrison’s Liberals, who hold just a one-seat majority, face a pincer movement from populist parties on the right, such as mining billionaire Clive Palmer’s United Australia, and progressive independent candidates in the party’s traditional wealthy urban strongholds standing on a climate platform.

The deeply religious Morrison defied the odds in 2019 to win a “miracle” election so few are writing off his chances next month. Grahame Morris, a former Liberal party director, said the polls would narrow but remained pessimistic about the government’s chances given the danger of a “monster swing” against the incumbent party.

“If the last one was a miracle then this one would be a miracle plus,” he said.