By Lord Ashcroft

What do we know about Boris Johnson? That he is the most popular politician in the country. That he raises the spirits in gloomy times. That he is a Tory who was elected, and then re-elected, in a predominantly Labour city. And that some think the magic that helped ensure his two personal victories would do the same for his party if, one day, he led it.

It is not a ridiculous idea. But in politics, things are seldom as straightforward as that. I decided to look further into the proposition that Boris is the answer. What is the nature of his appeal, and how far does it stretch beyond London? What do people think he believes, and does it matter? Does being a successful Mayor qualify him to lead a country? Would he boost his party’s popularity, or would it erode his own? What kind of voters are the most eager to see him in Downing Street, and who is more doubtful? And if Boris is the answer, what exactly is the question?

My poll of 8,000 people, together with focus groups in Eastleigh, Taunton, Huntingdon, Warrington, Nuneaton and Leeds, showed that Boris’s popularity is by no means confined to the capital. He was thought more likely than any other senior politician to be strong, likeable, a “people person”, up to the job, a winner, and someone who gets things done.

Majorities in all regions apart from Scotland thought him “different from most politicians, and in a good way”. We asked for the first word or phrase that came into people’s minds when they thought of Boris; the collected answers largely paint a picture of fondness and sometimes even admiration that is unique for a contemporary politician.

Boris is also the second most recognised politician in Britain, after the Prime Minister. In a world where only 72% can correctly identify a picture of Nick Clegg (most often confusing him with George Osborne), 62% can accurately name an image of the Chancellor (most often confusing him with Ed Miliband), 64% correctly name a photo of William Hague (most often confusing him with Iain Duncan Smith, and sometimes with Ross Kemp), 55% can put the right name to Theresa May (most often confusing her with Harriet Harman), and only one in ten can correctly identify Philip Hammond (most often muddling him up with Jeremy Hunt, and sometimes with Julian Assange), it is quite something that Boris achieves recognition above 90%.

Two thirds of voters, including majorities of all parties’ supporters, thought Boris was doing well as Mayor of London. But while just over half in our poll thought being Mayor was a serious job and that Boris had shown he could take on real responsibility, 42% thought the job was “mainly about generating publicity for the city rather than running anything”. People in the groups often referred to him as the Lord Mayor, and many assumed the role was mainly ceremonial or ambassadorial; though they thought he did a brilliant job of promoting the city, many were surprised to learn he had executive authority in important areas like transport and policing.

Most knew about Boris’s prosperous background but this hardly ever mattered to people; wherever he came from, he seemed be in touch and down to earth. People often remarked that he regularly managed to get himself into trouble, though few could recall specific incidents. Reminding them helped prove that Boris is given the benefit of the doubt to an extent that other politicians can only dream of. While people will reflexively question the motives and intentions of MPs for saying and doing the most straightforward things, most of our participants went out of their way to put a generous interpretation on the most controversial episodes in Boris’s career. Though they often knew he led a colourful private life, they strongly agreed with him that this was none of their business.

Despite the impression that he speaks his mind, most people were at a loss to say where he stood politically, either in general or on any particular issue. If pushed to guess, people usually said he probably wanted a tougher immigration policy and was in favour of gay marriage, but they were unsure about his views on Europe: in the poll, 30% said they thought he wanted to stay in the EU, 27% thought he wanted to leave, and the rest didn’t know. Similarly, though people often said he refused to toe the party line, nobody could remember an instance of him disagreeing with David Cameron or the government.

In the focus groups, the prospect of Boris one day becoming Prime Minister was usually raised by participants themselves; it was to them an obvious part of any conversation about him. When asked who would make the best PM, each of the three party leaders or Boris, David Cameron came out narrowly ahead on 33%, two points ahead of Ed Miliband, four points ahead of Boris and 26 points ahead of Clegg. Among Conservatives, Cameron was the clear winner over Boris, by 81% to 18%. UKIP supporters were the only group among whom Boris was the favourite.

When we asked about how they would handle different aspects of the job, Boris beat Cameron only on “understanding ordinary people” (and Miliband beat them both). Cameron was the clear leader when it came to representing Britain internationally, making the right decisions even when they are unpopular, leading a team and doing the job overall. There was less to choose between the three on “having a clear idea of what they want to achieve”, presumably more because it seemed equally untrue of them than equally true.

Only just over a third of voters overall, including around half of Conservative and UKIP supporters, said in the poll that Boris would be “capable of running the country as Prime Minister”. As the groups helped to show, this hides a more nuanced set of thoughts. For some it was conceivable that he could do the job as the Boris they thought they knew, doing the “showbiz” while others conducted the serious business. They felt this would carry the potential for disastrous or at least hilarious consequences, which is why many felt the Conservative Party would never take the risk of installing him as leader. The more prevalent view was that in Downing Street Boris would have to tone down his approach, and would have more limited scope to say what he thought – in which case he would lose much of what appealed to people about him in the first place.

Asked whether they would be more or less likely to vote Conservative if Boris were leader, half said it would make no difference; just under a quarter said it would make them more likely. UKIP supporters were the most inclined to say they would be more likely to vote Tory with Boris in charge. Lib Dem voters were equally divided as to whether he would make them more or less likely to vote Conservative, and more Labour voters said he would reduce the chances of them voting Tory than that he would raise them. UKIP voters and those aged 18 to 24 were the only groups among whom a majority thought the Conservative Party would be more likely to win a general election if Boris led it.

The overlap between UKIP-inclined voters and those who most strongly back the idea of Boris as Prime Minister is surely no coincidence. The fact that Boris has been among the most outspoken supporters of immigration and gay marriage shows that this is nothing whatsoever to do with policy. Instead it shows that people’s stated desire to see him in Number 10 says less about Boris himself than it says about them, and crucially their own view of politics and political leadership.

Those for whom politics is the hard grind of sorting out difficult problems most value competence and statesmanship and want to be able to picture their leaders in the company of Obama and Merkel. (That is not to say Boris lacks these qualities, rather that they are not the things they most closely associate with him). Existing Conservative supporters largely fall into this group; they have after all signed up to the drudgery of deficit reduction. This helps explain why, adore Boris though they do, they much prefer the idea of Cameron as Prime Minister, and fewer of them than average think the party would be more likely to win an election with Boris as leader.

The idea of Prime Minister Boris appeals most to those who have the most jaded view of what politics can achieve for the country and themselves. Though they often think Boris is cleverer and more competent than he is sometimes given credit for, this is beside the point. It is the antithesis of the idea that serious times call for serious people; rather, in an age when our problems seem beyond the capacity of governments to solve, we might as well have a leader who cheers us all up.

In electoral terms, the question is whether Boris as leader would win for the Conservatives voters from Labour and the Lib Dems, and those who have moved to UKIP or stopped voting altogether. For those on the fringe, one of the big attractions of Boris (as of UKIP) is that he is ‘none of the above’: this lot are no good; if only we could put someone else in charge. Once there, though, would Boris make mainstream politics attractive to those who have rejected it? More likely, the slog and compromise of it all would dull for them the Borissian lustre. As Mayor he can claim the credit for some real achievements, while the fact that times are hard is not his responsibility. But in government, or when asking people to put him in government, he would find the blame for all sorts of things laid at his door. The benefit of the doubt would be harder to come by.

In his London campaigns Boris undeniably attracted voters who usually support other parties. As our research shows, this would be less likely to work in a general election. Otherwise Labour and Lib Dem supporting voters backed Boris as Mayor on a personal mandate and a personal manifesto; for many, the fact that he was a Tory was incidental. Asking them to vote for a Conservative government, inhabited by the Conservative Party and implementing Conservative policies but with Boris at the helm, would be a rather different proposition. The uncommitted and uninterested, meanwhile, would give him a hearing, but Boris alone would not be a good enough reason for them to vote Tory.

There is no doubt that Boris is a great asset to his party, and I think his time as Mayor has shown that he is up to the demands of executive office. But ultimately, were it to come to pass, the fact of having Boris as leader would not make the things that stop people voting Tory go away, and it would be a gamble to assume he would trump them. The question “are you serious?” would not just be one the voters asked of Boris: it would demand an answer of a party that thought an entertaining new leader would be enough by itself to win them over.