Tuesday afternoon found the Spanish prime minister, Pedro Sánchez, in the senate, reflecting on what could charitably be termed his opponents’ antipathy towards his socialist PSOE government.

“I know you think I’m a dangerous, extreme leftwinger who’s trying to break Spain apart,” he told the spokesman for the conservative People’s party (PP). “I know that everything I do, and everything my government does, is illegal, immoral and even fattening.”

The ironic outburst came in reply to a question about what his administration had done to fix Spanish democracy since using public anger and a motion of no-confidence to kick the PP out of power at the end of May.

But he could have used it again the following day when the new PP leader, Pablo Casado, accused him of yielding to the Catalan independence movement by enlisting the backing of nationalist parties in the no-confidence vote.

“You are participating in, and responsible for, the coup d’état that’s being carried out in Spain,” said Casado.

The accusation, which stirred memories of the failed coup against Spain’s young democracy in 1981, was inflammatory but not wholly surprising. Almost five months after Sánchez entered the Moncloa palace, political temperatures are running very high and the PSOE’s honeymoon – such as it was – is well and truly over.

Sánchez tabled the no-confidence motion promising to “do away with this corruption thriller into which the People’s party has plunged our politics” and to focus on what mattered to Spaniards.

Its success put an end to Mariano Rajoy’s scandal-ridden tenure as prime minister and had the added benefit of utterly wrong-footing the centre-right Citizens party, which had been leading the polls.

Since then, however, Sánchez’s government has been plagued by its own scandals. The first majority-female cabinet since Spain’s return to democracy – 11 women and seven men – has been hit by two resignations. The journalist and writer Màxim Huerta quit as culture minister a week after he was appointed, after reports he had avoided paying taxes while working on TV a decade ago.

Last month the health minister, Carmen Montón, resigned after becoming the latest senior politician to find her educational qualifications under scrutiny.

Sánchez’s own academic credentials have been queried, and he went as far as publishing his doctoral thesis online to put an end to allegations of plagiarism.

Another three cabinet members – the justice minister, Dolores Delgado, the science minister, Pedro Duque, and the foreign minister, Josep Borrell – have also faced scrutiny from the media and other parties.

The PSOE’s critics and opponents have seized on such cases in an attempt to inflict further damage on Sánchez’s minority government. The party has only 84 of the 350 seats in the congress of deputies.

In recent weeks the government has pressed ahead with the sale of laser-guided bombs to Saudi Arabia – despite concerns over the use of such weapons in the war in Yemen – and it has stood by defence sales to the kingdom even after what it called the “terrible murder” of the journalist Jamal Khashoggi.

And yet for all that, not to mention the personal criticism of Sánchez – too PR-savvy (in marked contrast to his awkward predecessor), too fond of flights on the prime ministerial plane – there have been bold moves from one of Europe’s few remaining centre-left governments.

The decision to welcome the 630 people rescued by the NGO ship Aquarius may have been used against the government as immigration surged, but it won plaudits around the world.

Sánchez has committed his government to exhuming General Franco’s remains from his tomb in the Valley of the Fallen in an attempt to help Spain comes to terms with the enduring effects of the dictatorship, and he has signed a deal to bring about a 22% rise in the minimum wage.

It remains to be seen, though, whether Franco will yet end up reinterred in Madrid’s cathedral and whether the PSOE will get its 2019 budget passed.

The Catalan independence crisis, which dominated Rajoy’s final months in office along with the corruption scandals, has calmed down for the time being, although the lowering of tensions probably has more to do with the paralysis and fractures among the separatists than Sánchez’s measured and conciliatory approach.

Sánchez has backtracked on promises to hold early elections after the no-confidence vote, saying he wants to see out the legislature, which ends in 2020.

Recent polls tell an intriguing story. With the PP and Citizens party in open competition and swinging further to the right after the emergence of the tiny, extreme-right Vox party, the socialists would still win the most votes were an election held tomorrow.

A survey last week by the polling firm Metroscopia showed the PSOE taking 25.2% of the vote, the PP 22.6%, Citizens 19.2% and the far-left, anti-austerity Unidos Podemos 17.7%.

Another poll, released on Thursday by Spain’s Centre for Sociological Research, put the PSOE even further ahead, on 31.6%. The Citizens party was in second place on 21%, leapfrogging the PP on 18.2%, while Unidos Podemos was on 17.3%.

“You need to remember that before the vote of no confidence, the PSOE wasn’t even second in the polls, it was third,” said José Pablo Ferrándiz, Metroscopia’s chief researcher.

“But in the run-up to the motion of no confidence, there was a sense – even among PP voters – that a change was needed, and there was a drive to remove Mariano Rajoy from office. What the motion did was allow the PSOE to portray itself as the biggest political force because its leader was seen as the person who had managed to get rid of Rajoy.

“It’s about that sense of relief – and about the divisions suddenly erupting on the right.”