Here is why Ms. Clinton is still odds-on favorite to become the first female President of the U.S., along with a few reasons why a dose of caution might be warranted.

In a U.S. election that has ripped up, chewed through and spat out conventional wisdom, Hillary Clinton is still prohibitive favourite to beat Donald Trump in November.

Few analysts or journalists predicted that Mr. Trump — a blustering mogul with less political experience than Katy Perry — would last long in a tough Republican race, much less win it.

But here is why Ms. Clinton is still odds-on favorite to become the first female President, along with a few reasons why a dose of caution might be warranted.

The numbers

At the starting gate, a CNN/ORC poll has Ms. Clinton leading Mr. Trump 54-41. For months, head-to-head surveys have found a similar result.

That is a monumental lead in a country almost evenly split between the Democrats and the Republicans. But it is also borderline irrelevant.

The November 8, 2016 vote is six months away, light years in U.S. electoral politics.

And U.S. elections are won by carrying individual States, not the popular vote, as Al Gore found to his cost in 2000.

Still, the polls contain harbingers of doom for Mr. Trump, particularly in a sliver of data that politicos refer to as “unfavourables”

About 65 per cent of voters have a negative impression of Mr. Trump, according to an average of polls by Real Clear Politics.

Given he has been in the public eye for years, he is widely known and minds could be difficult to shift.

Yet “The Donald” has shown he does not play by conventional election rules.

He has already branded his rival “Crooked Hillary” and is certain to stir up memories of Bill Clinton’s marital infidelity.

Ms. Clinton who is herself seen negatively by 55 per cent of voters — a large number, but not quite as catastrophic as Mr. Trump’s — has the upper hand, but will have to find the right tone to parry attacks.

Mr. Trump’s rivals learned the hard way that getting in the mud with him rarely pays off, but taking the high road might look detached or meek.

The electorate’

The long trend of America becoming less white means Mr. Trump, with his pseudo-nativist message, is also waging a campaign against demographics.

In the 2012 election, 93 per cent of African-Americans, 71 per cent of Hispanics and 73 per cent of Asians voted for Barack Obama.

That was enough for the Democrat to win the election, even though he only got 39 per cent of white voters, the biggest voting group.

Mr. Trump — thanks to talk of building a border wall, Mexican “rapists” and deporting the country’s estimated 11 million illegal immigrants — is doing even worse among Hispanic voters than the last Republican presidential candidate Mitt Romney.

His approval ratings among Hispanic voters currently stand at 12 per cent.

That’s bad news for Mr. Trump’s chances in Colorado, Florida, Nevada, New Mexico and maybe even Arizona. To add to Mr. Trump’s misery, his standing among women voters is derisory.

Almost half of Republican women say they can’t see themselves voting for him.

“Trump has alienated growing demographic groups such as Hispanics, and he is at toxic levels with women and young people,” said Larry Sabato, who heads the University of Virginia Centre for Politics.

If he can’t reach working and college educated women, then even blue collar states like Pennsylvania may remain out of reach.

Mr. Trump hopes to change the calculus by getting more white voters to turn out.

“He needs to excite the middle and working class white who doesn’t usually vote,” said Henry Olsen, a senior fellow at the Ethics and Public Policy Centre.

Mr. Sabato was skeptical.

“There aren’t millions of blue collar whites who don’t usually vote Republican just waiting to show up for Trump. Where’s the evidence for this breathtaking proposition?”

The Map

The most important number in U.S. politics is 270, the number of electoral college votes — out of a total of 538 — needed to win the presidency.

Of the 51 State and regional contests, most are winner-take-all. But not all are equal.

California is worth 55 votes, while Vermont is worth three.

In 2008 and 2012, Mr. Obama broke 300.

The last Republican President, George W. Bush, squeaked by with 271 and 286.

Mr. Trump may target States in the Rust Belt and New England, and battlegrounds like Florida and Ohio, but he faces the prospect of having to flip several states to the Republican column just to be competitive.

The campaigns

The businessman will have to try to do all this without the unified support of the Republican party.

There have been mass refusals to back the controversial candidate.

Many donors and potential campaign staff promise to “sit this one out”.

To give one example of the impact, Hacking the Electorate author Eitan Hersh said Mr. Trump will find it more difficult to get targeted messages to voters.

A key arrow in the quiver of modern U.S. electoral campaigns is micro-targeting — cross-referencing voter rolls with records on everything from magazine subscriptions to eBay searches to build a profile of individual voters and deliver a specific message.

Mr. Trump has instead focused on macro-messaging, by dominating the TV news which also gives him free advertising.

“Mr. Trump hasn’t shown much of an appetite to engage in micro-targeting. He also is not a team player,” said Mr. Hersh.

“Part of the Democrats’ advantage is that the State parties, interest groups, labour unions and candidates up and down the ballot see themselves as largely on the same team.”

The zeitgeist

One area where Mr. Trump may have an advantage is capturing the spirit of the age.

Many Americans still feel the effects of the Great Recession.

Middle class incomes have been stagnant, while the rich have become significantly richer.

Democrats are not oblivious to that fact, indeed Bernie Sanders has built most of his campaign around addressing income inequality.

But Mr. Trump may better articulate the fear and anger of those who have faltered.

After years of modest growth, a mediocre jobs report in April was a reminder that another slowdown could come even before the impact of the last one is no longer felt.

That could easily eat into Mr. Obama’s solid 51 per cent approval rating, a metric that currently indicates the electorate is not desperate for a changing of the guard.

Along with the economy, polls show terrorism is a top concern for voters.

Here too, Mr. Trump’s message of bombing the Islamic State group to oblivion is more easily digested than Ms. Clinton’s more nuanced push for tackling radicalism through military, economic, diplomatic and cultural means.

Where rivals see him as naive, Mr. Trump’s status as a political neophyte might serve him well.

It’s harder for Ms. Clinton, a former first lady, U.S. Senator and Secretary of State to argue that she will bring change to Washington.

But her wealth of experience might also mean she knows a bit more about winning elections.