NEW Yorkers have witnessed bare knuckle fights before, but this one could get ugly as two of its own slug it out over the next five months for the keys to the White House and the most powerful political job in the world as US President.

America will have to decide whether to return Hillary Clinton to the home she once inhabited with husband Bill or to entrust the nation and, some could argue, the world with Donald Trump.

He started the campaign as a 160/1 outsider, a joke candidate many predicted would fail to even make it through the Republican primaries. But having headbutted his way to within touching distance of achieving the once unthinkable, 9/4 is as high as it gets now.

Clinton, though, has had to claw her way to securing the Democratic nomination. Even now with numerical supremacy and the expected endorsement of a sitting president, some backroom deals and promises need to be given for peace of mind.

She lost out eight years ago. It will have stung then. Meantime she needs to play catch up to Trump who, having secured his party’s nomination much earlier, has switched from street-fighting rhetoric to well-honed messages about the economy.

Unlike Barack Obama who swept into power as the first black president in US history full of relative youth, vigour and dreams of a nation, Trump - who turns 70 in a few days - and Clinton, 69, will be a different bag of bones.

But come November 8, history will be made one way or another.

HOW DID WE GET HERE?

It’s the end of Barack Obama’s second term in office. His audacity to hope delivered so called Obamacare, opened up roads to Cuba, nailed Osama Bin Laden, withdrew US troops from Iraq and struck a deal on nukes with Iran.

But his unfinished business needs to be taken up, or even undone, by the next President such is the US constitution.

Clinton becomes the first woman to lead a major American political party and is already casting herself as the beneficiary of generations who fought for equality.

“This campaign is about making sure there are no ceilings, no limits on any of us,” she said.

Trump secured the presumptive nomination in May with a crushing win in Indiana.

He said: “We’re going to win in November and we’re going to win big and it’s going to be America first.”

A year ago he announced his candidacy with an attack on Mexicans, vowing to build a wall along the US border, saying: “They’re bringing drugs. They’re bringing crime. They’re rapists. And some, I assume, are good people.”

He then turned his attack on journalists, had people thrown out of rallies who dared protest against him, and rounded on TV host Megyn Kelly when she challenged him on his view of women as “fat pigs, dogs, slobs and disgusting animals”.

Even his own side got involved with rival candidate Ted Cruz branding him “a pathological liar”, and “utterly amoral”.

Clinton faced past demons, when she was grilled over the controversial terror attacks in Benghazi as secretary of state.

She also remains embroiled in a row over thousands of emails from her private account which some say flouted secrecy rules.

BUT WHAT ABOUT BERNIE?

Clinton’s closest rival Bernie Sanders said he was “really disappointed” and “upset” when The Associated Press declared her the presumptive Democratic nominee early this week.

Yet in the eyes of many, he is already a winner, having come from nowhere to within a heartbeat of the nomination. Clinton for her part has scheduled a meeting with Sanders in the coming days to “look at the road ahead”.

He is set to meet President Obama today, and it won’t have been lost on anyone how Sanders has gone from being a relative nobody to a tour de force funded largely by a youthful support and micropayment campaign.

Perhaps we’ve not heard the last of him just yet.

But this is a race littered with the political dead.

Former Texas governor Rick Perry was first to fall in September last year, followed by Wisconsin governor Scott Walker, former US senator Jim Webb and Rhode Island governor Lincoln Chafee in October.

The following few months saw the end of the road for Harvard professor Lawrence Lessig, Louisiana governor Bobby Jindal, US senator Lindsey Graham, former New York Governor George Pataki, the former Maryland governor Martin O’Malley and Mike Huckabee of Arkansas.

Others hung on in there a little longer, including US senator Rand Paul, former senator Rick Santorum, the New Jersey governor Chris Christie, the former Virginia governor Jim Gilmour and Carly Fiorina, a former business executive who was the only other woman hopeful in the race.

But the hardest goodbyes perhaps came from former Florida governor Jeb Bush, retired brain surgeon Ben Carson, Florida senator Marco Rubio, Texas senator Ted Cruz and Ohio governor John Kasich.

WHO WILL WIN?

Democrats might want to look away now because the party doesn’t have a great history in passing the flame from one sitting member to another.

In fact you need to go all the way back to 1857 and James Buchanan, who sat in the Oval Office until 1861, for the last time that happened when he replaced Franklin Pierce.

Clinton has, of course, been on the political circuit for most of her adult life. Some argue she will woo the women’s vote too.

But she has had baggage and trust issues to overcome.

It could come down to a straight fight not just about politics but personality. Just which of the two will America like or dislike the most?

Trump, other than his controversial nature which still threatens to split his party’s support through the middle, has a curious piece of history to flip too.

No-one has been elected to President without any experience in Congress or as a governor in more than 60 years. The last one was Dwight Eisenhower.

He argues his experience running casinos and other businesses is proof that he is a dealmaker. This could be his biggest bet yet.

The RealClear Politics poll of polls over the past 10 months suggests Clinton has the edge with voters on 46.7% over Trump on 40.5%. That’s a long way off her highest poll of 53.3% on July 1. Tellingly, Trump is yet to poll higher than 44.3%.

WHAT HAPPENS NEXT?

The gloves come off. Trump has promised a major speech next week on Clinton and her husband, former President Bill.

Unless there is a shock from within the party itself, Trump will be endorsed at the Republican National Convention in Cleveland on July 18. Clinton has her first date with destiny during the Democratic National Convention in Philadelphia on July 26.

Both go into full campaign mode until a first TV head-to-head in Ohio on September 28, Missouri on October 9 and for a final time in Las Vegas – the casino capital of the world – on October 19.

By then all bets could be off.