By Branwen Jeffreys
Health correspondent, BBC News
David Cameron has played on his son Ivan's (l) NHS experience
Within a month of becoming party leader David Cameron made his first major policy speech on health, with a commitment to a tax-funded service free at the point of use.
It was the first salvo in some bold campaigning on the NHS, featuring issues such as infections and hospital reorganisations, which polling suggests has increased public confidence in the party's ability to safeguard the health service.
The party has been able to tap into public unease at change in the health service, particularly in England.
It has backed campaigns to save district general hospitals from being downgraded and suggested thousands of GP surgeries may be under threat from plans for polyclinics or GP-led health centres.
These are both issues which have galvanised local communities, with some hospital petitions and marches attracting many thousands of people.
These are policy positions defined in opposition to Labour in England, but nonetheless effective politically for that.
David Cameron has played strongly on his contact with the service through his son Ivan, who is severely disabled, to make a personal claim to understand the public affection for the NHS.
The Conservatives claim to offer a more efficient NHS which places more trust in professionals and places less emphasis on centrally-set targets.
This tacitly recognises the remarkably small gap on many issues between Labour health policy in England and the Conservatives.
Instead it focuses on the debate about whether the NHS is delivering enough in return for the record investment of the last few years.
Or, as David Cameron has said about health policy: "Let's not create differences where there are none."
On issues such as the use of the private sector under contract to the NHS, patient choice, foundation hospitals and GP-led commissioning, the party wants to see the health service go further.
If you want a different approach to the NHS, you are more likely to find it outside England.
Where health has been devolved, the policy gap has widened.
Both the SNP and the One Wales administration are committed to phasing out the use of the private sector.
So the amount of clear blue water you will see as a voter very much depends on where in the UK you live.
So where in all of this is the vision?
This week the Conservatives have launched a policy paper on their plans to move towards measuring the success of the NHS in England less against central targets and more against outcomes for patients.
That might mean, for example, more monitoring of five-year survival rates for cancers, and less of how well hospitals meet targets for Accident and Emergency waiting times.
Although the case behind this shift has been set out in more detail this week, this is not a new Conservative policy.
In 2004 the party promised to get rid of centrally-imposed targets for hospitals. This is a policy area which deserves closer scrutiny.
The public remain concerned about hospital infections, Tories say
The case against targets is that they have been costly and sometimes have perverse effects.
On the other hand, partly as a result of targets, the maximum waiting time for hospital treatment is coming down in every part of the UK.
The Conservatives have tapped into public concern about hospital-acquired infections in their campaigns.
It is not clear for example if they would go as far as scrapping the various existing targets to reduce them.
What is new is a promise to measure NHS performance against some international benchmarks - making five-year survival rates for cancer better than the EU average by 2015 and bringing deaths preventable by healthcare into line with the rates in similar countries.
Some progress on both is already being made, so this may amount mainly to a promise to press ahead with the speed of improvement.
The rate of progress on mortality preventable by healthcare is already faster than in other similar countries, according to a recent report by the Nuffield Trust.
It is fair to say that these broad aims are less prescriptive than the existing targets for hospitals as they rely on the performance of the health service as a whole.
Some of the existing targets will have expired by the time of the next election.
The Conservatives say they want "more trust" in NHS professionals
If waiting comes down to a minimal level in the next few years, then the suggestion of a move towards measuring quality of care for patients may well be welcomed by professionals.
One other area of radical thinking the party has done so far is in public health - an area of policy less visible to most voters, but essential for managing the ill health caused by our lifestyles.
Public health budgets, which are mainly spent on education and prevention, are vulnerable to being squeezed when the health services finances tighten.
The party is promising separate budgets to prevent this happening, and a stronger role for public health doctors in each local area.