Former president Luiz Inacio Lula da Silva greets followers during a political rally for the election of the Workers’ Party (PT) candidate for governor of Acre state and the re-election of president Dilma Rousseff, in Rio Branco.

He remains the one true rock star of Brazilian politics, introduced to an adoring crowd of thousands over the weekend as “our eternal president”.

Luiz Inacio Lula da Silva, 68, is back on the campaign trail after a brief hiatus, hoping that a burst of his signature charisma and rapport with the poor will be enough to push his chosen successor, president Dilma Rousseff, to a re-election victory in a closely fought runoff vote on Sunday.

The emcee’s introduction at a rally in Belo Horizonte on Saturday also touched, intentionally or not, on an intriguing subplot - whether Lula, who oversaw an economic boom as president from 2003 to 2010, is laying the groundwork for his own return as a candidate in 2018.

For now, though, the focus is firmly on whether the gravelly voiced former union leader whom US President Barack Obama once called “the most popular politician on earth” can help Rousseff eke out a victory despite an economy that has slowed sharply since Lula left office.

While some believe Lula’s star has faded a bit amid Brazil’s recent troubles, others say his support is just what’s needed to push Rousseff over the top.

Around 6% of voters remain undecided, polls show. More than half of them are from Brazil’s poorest demographic, in households earning less than $700 a month, many of whom still regard Lula as the only politician of relevance in their lives.

Lula’s recent appearances, part of a nationwide tour that will see him stump by Rousseff’s side, also helped ease concerns that a brief break from campaigning last week may have been the result of tensions between him and Rousseff, as numerous reports in Brazilian media suggested.

There was no sign of any ill will on Saturday.

Stalking the stage, kissing babies and alternating between whispered jokes and roars of indignation, Lula, who was himself born into dire poverty, said a vote for Rousseff is the only way to ensure the social gains of recent years continue.

His biggest applause line was an attack on Neves, a former state governor and scion of a political dynasty who Lula and Rousseff have repeatedly cast as a tool of the elite.

“He has the behavior of a daddy’s boy who always thinks that others have to do everything for him, who looks down his nose,” Lula bellowed, as the flag-waving crowd went wild.

Lula stuck with that rich-versus-poor theme during his 33-minute speech, slamming bankers and the media while also mocking the British newspaper The Economist - “That’s a chic name, isn’t it?” he joked, to titters from the audience - for its recent endorsement of Neves.

“It makes (the rich) uncomfortable now that the poor can have things,” Lula said. “We used to be happy with chicken feet. Now we want chicken breasts!”

Lula’s earthy rhetoric is particularly helpful for Rousseff, a lifelong civil servant who was born into a privileged family and has always struggled to connect with the masses.

The stark difference between their styles has provoked nostalgia from many Workers’ Party faithful, some of whom never fully embraced Rousseff and openly wish Lula was the candidate again this time around.

“He’s old but he’s still the best, like Mick Jagger up there,” said Jonny Guimarães, 62, a university professor. “If it was him (running), we wouldn’t have such a close election.”

The constitution prevented Lula from running for a third consecutive term in 2010, so he plucked Rousseff, then his chief of staff, from relative obscurity and helped her win the vote, aided by an economy that boomed 7.5% that year.

Since then, growth has averaged less than 2% a year, due in part to lower prices for Brazilian commodities like iron ore but also Rousseff’s more heavy-handed approach to economic policymaking, which has alienated many investors.

In contrast, one of Lula’s great talents as president was that he quietly made both rich and poor happy. Even as he slammed bankers at the rally on Saturday, he noted they also profited from the rising economic tide that lifted some 35mn people from poverty since he took office.

“We did all this without taking anything away from anybody,” he said, wagging his finger at the crowd.

The constant comparisons with Rousseff - and the drumbeat for Lula to run again, which the constitution would allow - have caused bad blood in both camps.

When Lula took a few days off for “rest” following the first round of voting on October 5, Brazilian newspapers buzzed with talk that he was angry at Rousseff’s supposed refusal to heed his advice on the economy - or even distancing himself from her in case she might lose.

Lula’s spokesman, Jose Chrispiniano, said the relationship between the two is “fine” and that Brazilian media have been trying to drive a wedge between them for years.

A source from Lula’s inner circle told Reuters earlier this year that Lula does intend to run in 2018, assuming that his health remains good following a recovery from throat cancer that was diagnosed shortly after he left office.

The source also said that Lula would be more active in day-to-day policy decisions if Rousseff wins a second term.

“He won’t have to worry about overshadowing her anymore, since she won’t ever face another election,” the source said.

Rousseff told reporters last week that, if Lula runs again, “I’ll certainly help him.”

Some wonder whether he would ever be able to regain the magic of his first presidency.

In the first round of the election on Oct. 5, Rousseff lost in the industrial belt of Sao Paulo, where Lula first rose to prominence as a metalworkers’ union leader in the early 1980s. The area has been hard hit by a slump in manufacturing under Rousseff.

In a poll released last week by Datafolha, 37% of voters said Lula’s support would make them more likely to choose a candidate.

Still, that was nearly double the number who said the same thing of popular environmentalist Marina Silva, who fell out of the race when she placed third in the first round of voting and has granted a coveted endorsement to Neves in the runoff.

Gilda dos Santos, a 41-year-old unemployed maid, said after attending Lula’s speech that she and others who receive monthly payments under the vaunted social welfare programmes that Lula greatly expanded would “follow him anywhere.”

“I don’t like (Rousseff) much, but I love Lula,” Dos Santos said. “He helped us. No other politician ever has.”

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