Hoping to see the same kind of backlash that in March saw Swiss voters back a ban on golden handshakes in the business world, the left-wing campaigners behind the "1:12" initiative are working round the clock ahead of the November 24th plebiscite.
The 1:12 label refers to the ratio between the lowest and highest salaries in companies, which the referendum spearheaded by the youth wing of the Swiss Socialist Party would lay down in the law.
"We're going to pull out all the stops," David Roth, head of the youth wing, told AFP.
To hammer home their message, the campaigners have opted for guerrila marketing tactics in Switzerland's financial hub Zurich, projecting images onto the building of banking giant UBS.
They also kicked off a "Fat Cat of the Week" campaign on their Facebook page, spotlighting the head of UBS's investment banking division Andrea Orcel.
Orcel's salary is 194 times higher than that of the lowest-paid UBS employee, they underlined.
The former Bank of America Merrill Lynch executive chairman, previously at Goldman Sachs, also received a 26-million Swiss franc ($29 million) golden handshake when he joined UBS in 2012.
The 1:12 proposal is opposed fiercely by the Swiss business world and the right and centre of the political spectrum, and had been expected to fall flat.
But a poll commissioned by Switzerland's public broadcaster SSR, released at the end of last week, showed that supporters and opponents on 44 percent each.
"It's better than previous polls which only gave 35 percent in favour," Roth said, though he cautioned that campaigners knew they still had their work cut out.
"It could still vary between 10 or 15 percent for each side," he explained.
Referendums are the cornerstone of Switzerland's system of direct democracy, and are held several times a year.
Most Swiss cast their ballots by post, and their voting papers are scheduled to be sent out next week, along with campaign material from the opposing camps.
With voters therefore weighing up their choices, Roth said his campaign team planned a massive rally in Zurich on November 2nd.
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