A total of 55 votes were cast by RMT members in a ballot for strike action against Eurostar, 52 of which said they would be "prepared to take strike action".
In a second vote, 48 of the 55 voted that they would be prepared to take "industrial action short of a strike".
The information was listed under "ballot results" on the RMT website.
The numbers seemed to escape union boss Mick Cash during a Sky News interview this morning.
When asked how many train managers were involved and how many voted in the strike, Cash was somewhat stumped.
"Oh blimey, now you are asking me a detail I haven't actually got. Because I have been dealing with the Southern Stuff," he said.
"I haven't got the answer to that question," RMT's Mick Cash said on how many Eurostar workers voted to strike https://t.co/fz2TzcqGT7
— Sky News (@SkyNews) August 10, 2016
According to the union, the dispute centres on Eurostar’s "failure to honour an agreement from 2008 which sought to ensure train managers could expect a good work-life balance in terms of unsocial hours and duty rosters".
The RMT has been approached for comment but a response has not yet been received.