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

From Tuesday, new guidelines on betting entered impact in Delaware, a tiny east coast state about 2 hours from Washington.

Neighbouring New Jersey might start accepting sports betting bets as early as Friday.

The changes are the first in what might become a wave of legalisation after the Supreme Court last month cleared the way for states to allow sports betting wagering.

The industry sees a "when in a generation" chance to establish a new market in sports betting-mad America, said Dublin-based monetary analyst David Jennings, who heads leisure research study at Davy.

For UK companies, which are grappling with combination, increased online competition and tougher rules from UK regulators, the timing is especially suitable.

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

"It's something that we're truly focusing on, but equally we do not desire to overhype it," said James Midmer, spokesman at Paddy Power Betfair, which recently purchased the US fantasy sports site FanDuel.

'Require time'

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

Firms are wishing to take advantage of more of that activity after last month's decision, which overruled a 1992 federal law that barred states outside of Nevada and a couple of others from authorising sports betting.

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

That is anticipated to lead to significant variation in how firms get accredited, where sports betting can happen, and which events are open to speculation - with big ramifications for the size of the market.

Potential income varieties from $4.2 bn to nearly $20bn annually depending upon factors like the number of states move 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 experts KPMG.

Now, he said: "I think many people ... are taking a look at this as, 'it's a chance but it's not going to be $20bn and it's going to be state by state and it's going to require time'."

'Remains to be seen"

Chris Grove, handling director at Eilers & Krejcik Gaming, forecasts that 32 states will legalise sports wagering in some kind by 2023, developing a market with about $6bn in yearly income.

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

US laws limited gambling largely to Native American lands and Nevada's Las Vegas strip up until reasonably recently.

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

States have actually also been slow to legalise lots of types of online gambling, regardless of a 2011 Justice Department viewpoint that appeared to remove challenges.

While sports betting is normally seen in its own category, "it clearly stays to be seen whether it gets the type of momentum people believe it will," said Keith Miller, law professor at Drake University and co-author of a book about sports betting wagering policy.

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

Now a consultant, he states UK firms ought to approach the market carefully, picking partners with caution and preventing bad moves that could cause regulator reaction.

"This is a chance for the American sports bettor ... I'm unsure whether it is a chance for business," he says. "It really depends on the result of [state] legislation and how the company operators pursue the opportunity."

'It will be partnerships'

As legalisation starts, sports betting wagering firms are lobbying to fend off high tax rates, as well as demands by US sports leagues, which wish to gather a portion of income as an "integrity cost".

International companies deal with the included difficulty of a powerful existing video gaming industry, with casino operators, state-run lottos and Native American tribes that are looking for to protect their turf.

Analysts say UK companies will require to strike collaborations, using their knowledge and technology in order to make inroads.

They indicate SBTech's recent announcement that it is offering technology for Kentucky Derby operator Churchill Downs as an example of the type of offers most likely to materialise.

"It will be a win-win for everyone, but it will be partnerships and it will be driven by technology," Mr Hawkley stated.

'It will just 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 a presence in Nevada.

William Hill now uses about 450 people in the US and has revealed collaborations with gambling establishments in Iowa and New Jersey.

It works as threat manager for the Delaware Lottery and has actually invested millions together with a local developer in a New Jersey horse racing track.

Mr Asher said William Hill has become a family name in Nevada however that's not necessarily the objective everywhere.

"We definitely intend to have an extremely substantial brand name presence in New Jersey," he stated. "In other states, it will just depend upon guideline and possibly who our regional partner is."

"The US is going to be the most significant sports betting wagering market on the planet," he added. "Obviously that's not going to happen on day one."