It's high stakes for UK firms as sports betting starts to spread out in America.

From Tuesday, new rules on wagering came into result in Delaware, a small east coast state about 2 hours from Washington.

Neighbouring New Jersey could start accepting sports bets as early as Friday.

The modifications are the first in what could end up being a wave of legalisation after the Supreme Court last month cleared the method for states to permit sports betting wagering.

The industry sees a "once in a generation" chance to develop a new market in sports-mad America, stated Dublin-based financial expert David Jennings, who heads leisure research at Davy.

For UK firms, which are grappling with debt consolidation, increased online competition and harder rules from UK regulators, the timing is particularly appropriate.

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But the industry says depending on the US remains a risky bet, as UK business face complex state-by-state policy and competitors from entrenched regional interests.

"It's something that we're actually focusing on, but similarly we don't want to overhype it," said James Midmer, spokesperson at Paddy Power Betfair, which just recently acquired the US dream sports website FanDuel.

'Take some time'

The US represented about 23% of the world's $244bn (₤ 182bn) in gaming income in 2015, according to a report by Technavio, external published in January.

Firms are wanting to take advantage of more of that activity after last month's decision, which overruled a 1992 federal law that barred states beyond Nevada and a few others from authorising sports wagering.

The ruling discovered the law was an over-reach of federal power. But the court it did not in fact legalise sports betting, leaving that concern to regional lawmakers.

That is anticipated to lead to substantial variation in how companies get licensed, where sports wagering can happen, and which events are open to speculation - with huge implications for the size of the market.

Potential earnings ranges from $4.2 bn to almost $20bn annually depending upon elements like the number of states transfer to legalise, Oxford Economics estimated in a 2017 study for the American Gaming Association.

"There was a great deal of 'this is going to be substantial'", stated Will Hawkley, London-based head of leisure for consultants KPMG.

Now, he said: "I think the majority of people ... are looking at this as, 'it's an opportunity however it's not going to be $20bn and it's going to be state by state and it's going to take some time'."

'Remains to be seen"

Chris Grove, managing director at Eilers & Krejcik Gaming, anticipates that 32 states will legalise sports betting in some kind by 2023, creating a market with about $6bn in annual revenue.

But bookmakers deal with a far various landscape in America than they perform in the UK, where wagering stores are a frequent sight.

US laws restricted gaming mostly to Native American lands and Nevada's Las Vegas strip up until reasonably recently.

In the popular imagination, sports wagering has actually long been linked to a 1919 baseball World Series match-fixing scandal.

States have actually likewise been slow to legalise many forms of online gambling, despite a 2011 Justice Department opinion that appeared to remove obstacles.

While sports betting is usually viewed in its own category, "it plainly remains to be seen whether it gets the type of momentum individuals think it will," said Keith Miller, law professor at Drake University and co-author of a book about sports betting policy.

David Carruthers is the previous primary executive of BetonSports, who was detained in the US in 2006 for running an overseas online sportsbook and served prison time.

Now a specialist, he says UK companies need to approach the marketplace carefully, picking partners with caution and preventing bad moves that could cause regulator backlash.

"This is an opportunity for the American sports gambler ... I'm uncertain whether it is a chance for company," he says. "It actually depends on the outcome of [state] legislation and how the service operators pursue the chance."

'It will be partnerships'

As legalisation begins, sports wagering companies are lobbying to ward off high tax rates, along with demands by US sports leagues, which want to gather a percentage of revenue as an "integrity charge".

International business deal with the added obstacle of an effective existing video gaming industry, with gambling establishment operators, state-run lottery games and Native American people that are seeking to defend their turf.

Analysts state UK firms will need to strike partnerships, offering their know-how and innovation in order to make inroads.

They indicate SBTech's current announcement that it is offering innovation for Kentucky Derby operator Churchill Downs as an example of the kind of deals likely to materialise.

"It will be a win-win for everyone, however it will be collaborations and it will be driven by innovation," Mr Hawkley stated.

'It will simply depend'

Joe Asher, chief executive at William Hill US, is clear-eyed about the truths.

The company has been buying the US market since 2011, when it acquired three US firms to develop an existence in Nevada.

William Hill now utilizes about 450 individuals in the US and has actually announced collaborations with gambling establishments in Iowa and New Jersey.

It works as danger manager for the Delaware Lottery and has invested millions together with a regional designer in a New Jersey horse racing track.

Mr Asher said William Hill has actually become a household name in Nevada but that's not necessarily the goal all over.

"We certainly mean to have a very considerable brand name existence in New Jersey," he stated. "In other states, it will just depend upon regulation and possibly who our local partner is."

"The US is going to be the biggest sports betting market worldwide," he included. "Obviously that's not going to happen on the first day."