* Sweden Democrats seen making large gains in elections
* Could rival biggest parties in size, polls suggest
* Party wants radical immigration clamp-down
* Akesson has revamped party image from skinhead days
* Leader is in "Viking rock" band https://youtu.be/a6hOUd1P2Ug
* Opinion poll graphic: https://tmsnrt.rs/2LmSZFD
By Niklas Pollard and Johan Ahlander
STOCKHOLM/VISBY, Sweden, July 12 - Once denounced as neo-fascists, Jimmie Akesson's Sweden Democrats look poised to translate more voter-friendly nationalist policies into big electoral gains in a country long famed for liberal tolerance.
In 1995, Akesson joined a tiny party supported by skinheads in steel-toed boots. Since he became leader in 2005, he has toned down the Sweden Democrats' image and broadened their appeal with his message that immigration is tearing the country apart.
Eight years after winning their first seats in parliament, the Sweden Democrats have upset a political order once defined by right- and left-wing blocs, and shaken the country's idea of itself as a progressive society.
Relaxed in a suit jacket but no tie, Akesson, 39, is watching a World Cup game on television in his corner office in parliament, a building where many had hoped he would never be let in. He is confident he can no longer be ignored.
"If we are the second biggest or biggest party in parliament and the other parties still believe we can be ignored, and pretend we don't exist, then we must flex our muscles," Akesson said in a Reuters interview.
Prime Minister Stefan Lofven called the Sweden Democrats neo-fascists in 2014, a charge they reject.
But events played into their hands during the refugee crisis of 2015, when Sweden took in 163,000 asylum-seekers, more than any other European country per capita. That put immigration firmly in the spotlight, where it has remained.
With opinion polls suggesting the Sweden Democrats may rival the biggest parties - Lofven's Social Democrats and the right-wing Moderates - at more than 20 percent of the vote in the election on Sept. 9, Akesson's years as a political pariah may soon be over.
(For a graphic, click https://tmsnrt.rs/2LmSZFD )
Many voters relate to his image of a Sweden weighed down by migrants, crime and a creaking welfare system, while his nationalist views coincide with populist gains in Europe and President Donald Trump vowing to put America first.
The party wants a freeze on most immigration and monetary incentives to persuade migrants to leave. It has also raised its profile in areas such as healthcare and crime.
"We are prepared to bring down any government we think is not leading Sweden in the right direction," Akesson said.
While his warning is stark, Akesson is low-key. A self-confessed introvert, he once wrote: "Anything you say can and will be used against you."
That was in his 2013 book "Satis Polito" - Latin for "polished enough", an indication of how he sees himself as an ordinary man confronting the political establishment.
Akesson speaks plainly and calmly, better suited to a Swedish audience that still cherishes consensus over conflict than the brash antagonism employed by leaders such as Trump. But his message is often as blunt as it is bleak.
As the foreign-born population has risen to 18 from 11 percent at the turn of the century, Akesson blames liberal immigration policies for gang violence, segregation, and riots in the high-rise suburbs ringing Sweden's biggest cities.
Akesson has said he wants to tear them down, while calling "Islamification" the biggest foreign threat since World War 2.
A fierce critic of the European Union, he wants a referendum on Swedish membership, though modest support for a "Swexit" means he has prioritised curbing immigration from elsewhere.
ROAD TO RESPECTABILITY
Akesson has been central to the evolution of the Sweden Democrats, according to Jonas Hinnfors, a political scientist at Gothenburg University.
"He has personified the transformation from bomber jackets and steel-toed boots to suits," Hinnfors said. "He has managed to formulate the party's core issues in a very skilful manner but also managed to avoid issues that are bad for the party."
After joining the Sweden Democrats in 1995, seven years after it was founded in part by activists with white supremacist links, Akesson and a close circle of friends, dubbed "the gang of four", set out to turn what he described as "a travelling circus" into a conventional party.
A burning torch party symbol mirroring that of the neo-fascist British National Front was replaced with a flower, while controversial demands, such as the reintroduction of capital punishment and limits on non-Nordic adoptions, were dropped.
Many have not accepted the changes at face value. When the Sweden Democrats won their first Riksdag seats, the Left Party refused to have their parliamentary office on the same floor, saying they felt unsafe in such company.
Leading a polarising party from obscurity into parliament has taken its toll. Threatened, and sometimes even egged, by opponents, Akesson lives under secret service protection and has been open about struggles with his mental health.
After the 2014 election, when the Sweden Democrats more than doubled their Riksdag seats to 49 out of 349, he went on sick leave due to burn-out.
"It's been very tough, not least because of the fierce social stigma of being a Sweden Democrat," said Mattias Karlsson, one of Akesson's "gang of four".
Though now the father of a son, Akesson's party work has eclipsed much else in his life - studies, career and relationships - and even to himself sometimes appeared a desperate gamble.
"Who would hire a former leader of a failed, scorned party stamped as racist?" he mused in a published journal entry dated 2010, before the party entered parliament.
Akesson's private life has largely been confined to other party members, with whom he goes on holiday. He is also the pianist in a band that plays so-called Viking rock - nostalgic, patriotic songs mixed with Norse mythology.
Having spent much of the early years all but ignored - he once drove 1,000 miles (1,600 km) to speak in front of four people - Akesson is even being talked about as possible future prime minister, though for now no other party would countenance it.
"Their wishful thinking is that the Sweden Democrats don't exist, that it's not for real, that we'll go away and everything will return to the old order. But that hasn't happened," he said. "I'm here."
(Reporting by Johan Ahlander and Niklas Pollard Editing by Giles Elgood)
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