Vote Leave target undecided voters over NHS
On day one, the official Leave campaign in the EU referendum chose to pick up not the issue of immigration, not the issue of sovereignty, not even the old chestnuts of rules and regulations from Brussels that drive some voters mad.
Instead, their banners unveiled this morning claimed that £350m a week of all our money is being channelled to the EU, and if we left, it could be spent on the NHS.
First, the claim itself is not entirely straightforward.
Yes, £350m of UK taxpayers' cash goes to the EU each week.
But much of the money comes back our way and is spent in the UK to support things like agriculture and research.
You can see the BBC Reality Check on the numbers here.
There have also been very serious warnings from unions, the health secretary and some health experts about the impact leaving the EU would have on the NHS.
Senior Leave campaigners acknowledge privately that the situation is a bit more complicated than the slogan on their banners would suggest.
At a campaign event in Manchester tonight, Boris Johnson just about admitted as much to me - although the pro-Leave audience was none too pleased that the question had been put.
But they have a very clear political reason for pushing the NHS, even thought it's not an issue you'd normally associate with the debate about the EU.
Sources in the campaign tell me that the ears of undecided voters prick up suddenly when they start talking about money that could, as they claim, otherwise be spent on the NHS.
The next part of the argument that appeals, they say, is that immigration is putting pressure on the NHS, and of course much of that strain is from EU migrants.
They argue it is the most effective way of getting undecided voters on their side.
And that is the task of the main Vote Leave campaign.
Champing at the bit
For some in the crowd in Manchester tonight, this referendum has been a very long time coming. Their votes are secure.
They are likely to be champing at the bit to come out and vote.
But those who will make the difference are the swathes of voters who are yet to make their minds up.
Vote Leave believes their arguments about the NHS just might get enough of them on side to get their campaign over the line.