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

From Tuesday, brand-new rules on wagering entered into effect in Delaware, a tiny east coast state about 2 hours from Washington.

Neighbouring New Jersey might begin accepting sports bets as early as Friday.

The changes are the first in what might end up being a wave of legalisation after the Supreme Court last month cleared the method for states to enable sports wagering.

The market sees a "when in a generation" opportunity to establish a new market in sports-mad America, said Dublin-based financial expert David Jennings, who heads leisure research at Davy.

For UK firms, which are coming to grips with consolidation, increased online competitors and harder guidelines from UK regulators, the timing is especially suitable.

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

"It's something that we're truly focusing on, however equally we don't wish to overhype it," said James Midmer, spokesman at Paddy Power Betfair, which just recently purchased the US dream sports website FanDuel.

'Take some time'

The US accounted for about 23% of the world's $244bn (₤ 182bn) in video gaming earnings last year, according to a report by Technavio, external released in January.

Firms are wishing to use more of that activity after last month's choice, which struck down a 1992 federal law that disallowed states beyond Nevada and a few others from authorising sports betting.

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 question to local lawmakers.

That is expected to lead to substantial variation in how firms get certified, where sports betting can take place, and which events are open to speculation - with big ramifications for the size of the marketplace.

Potential income ranges from $4.2 bn to nearly $20bn every year depending on factors like the number of states move to legalise, Oxford Economics estimated in a 2017 research study for the American Gaming Association.

"There was a lot of 'this is going to be big'", stated Will Hawkley, London-based head of leisure for experts KPMG.

Now, he stated: "I believe most individuals ... are taking a look at this as, 'it's an opportunity but 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 type by 2023, creating a market with about $6bn in yearly revenue.

But bookmakers face a far different landscape in America than they carry out in the UK, where betting shops are a frequent sight.

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

In the popular creativity, sports betting has long been connected to a 1919 baseball World Series match-fixing scandal.

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

While sports betting is usually seen in its own classification, "it plainly remains to be seen whether it gets the sort of momentum individuals think it will," said Keith Miller, law teacher at Drake University and co-author of a book about sports wagering guideline.

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

Now a consultant, he says UK companies must approach the market thoroughly, choosing partners with caution and avoiding missteps that might result in regulator backlash.

"This is a chance for the American sports gambler ... I'm unsure whether it is an opportunity for organization," he states. "It truly is reliant on the result of [state] legislation and how the service operators pursue the chance."

'It will be partnerships'

As legalisation begins, sports betting firms are lobbying to ward off high tax rates, as well as demands by US sports leagues, which desire to gather a portion of earnings as an "integrity charge".

International companies deal with the included obstacle of an effective existing video gaming market, with casino operators, state-run lottery games and Native American people that are looking for to defend their turf.

Analysts state UK firms will require to strike partnerships, offering their knowledge and innovation in order to make inroads.

They point to SBTech's current announcement that it is offering technology for Kentucky Derby operator Churchill Downs as an example of the sort 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 said.

'It will just depend'

Joe Asher, president at William Hill US, is clear-eyed about the realities.

The company has been investing in the US market considering that 2011, when it acquired three US firms to establish a presence in Nevada.

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

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

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

"We definitely plan to have an extremely substantial brand name existence in New Jersey," he said. "In other states, it will just depend upon regulation and potentially who our regional partner is."

"The US is going to be the most significant sports betting market in the world," he added. "Obviously that's not going to occur on the first day."