 He goes on to argue that the Leave campaign were offering such explanations, exemplified by the claim that £350 million a week could be spent on the NHS, regardless of whether or not this was a valid claim.One analysis of the Remain campaign has concluded that the campaign did little to counter Vote Leave's arguments surrounding immigration, an area that was considered one of Leave's biggest pulling factors in attracting voters.Furthermore, the official leaflet supplied by the government to make the case for remaining in the EU failed to address the issue of sovereignty, which was another area that Vote Leave was gaining a lot of support.