LONDON (Reuters) - As Britain’s “Brexit election” campaign swings into action, it may not be the country’s exit from the European Union which takes centre stage but another national obsession - the health service.

Prime Minister Boris Johnson has cast the Dec. 12 election as necessary to break the deadlock in parliament over Brexit, telling voters that only by returning his Conservatives with a majority can the country finally quit the European Union.

But many supporters of the opposition Labour Party, whose ambiguous position over Brexit has alienated some voters, believe the best chance of winning power is to focus the debate on other issues.

The state-run National Health Service (NHS), which has provided free at the point of use healthcare for more than 70 years, is a hugely emotive issue. Opinion polls consistently show voters cite it as the second biggest issue after Brexit.

Struggling under the pressure of record demand due to a growing and ageing population, as well as cut backs to social care services, the NHS has warned it faces a shortfall in funding despite government promises of extra money.

Despite its cherished status, complaints about long waiting times for consultations and operations, crumbling hospitals and staff shortages are a regular feature of public discourse.

Labour plan to make the NHS a big part of their campaign.

“This government has put our NHS into crisis, and this election is a once-in-a-generation chance to end privatisation in our NHS, give it the funding it needs,” Labour leader Jeremy Corbyn said on Wednesday, attacking Johnson in parliament.

Corbyn’s central charge: the NHS is at risk of being sold off to American corporations in any post-Brexit trade deal Johnson’s government does with U.S. President Donald Trump.

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“Labour won’t let Donald Trump get his hands on our National Health Service,” Corbyn said to cheers from the audience at his campaign launch in southwest London on Thursday.

“Quite bluntly, it’s not for sale,” he said, as the crowd rose to its feet and chanted: “Not for sale, not for sale.”

Johnson has repeatedly said the NHS would not be on the table in any trade talks but opposition lawmakers say they do not trust him.

Trump, who said during a visit to Britain in June that everything including health would be on the table in trade talks but then backtracked and said health would not be, told LBC radio that Corbyn’s claim was ridiculous and he did not know where it came from.

Asked about whether the health service would be up for grabs in trade talks, Trump said: “No, not at all, we wouldn’t even be involved in that, no.”

“No. It’s not for us to have anything to do with your healthcare system,” he said. “No, we’re just talking about trade.”

WINTER CRISIS?

The face of a “Leave” campaign which promised to spend the money Britain sends to the EU on the NHS instead, Johnson’s message to voters is he would deliver Brexit so Britain can move on to focus on priorities such as health, education and policing.

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“BackBoris for more NHS funding so that you and your family get the care you need,” the Conservatives said on Twitter, as Johnson visited a hospital on his first day of campaigning. He has done at least 9 hospital visits since taking office in July.

During one such visit he was confronted by a Labour activist and father of a sick child, who said the care his baby daughter had received had not been acceptable and that the health service had been destroyed by the Conservatives.

The NHS led two newspaper front pages on Thursday, with the Labour-supporting Daily Mirror splashing: “Election warning: Boris and Trump plot NHS sell-off”, while the pro-Conservative Daily Mail read: “Poll: Boris more trusted than Corbyn on NHS”.

Created by a Labour government in 1948, the NHS is one of the biggest employers in the world and in 2019-20 is due to account for 166 billion pounds ($215.04 billion), or around 20 percent, of Britain’s annual public spending.

It has traditionally been strong ground for Labour, with polls usually showing them as more trusted on the NHS. A December election, Britain’s first winter vote since 1923, could play to that strength.

Pressure on the NHS increases during the winter months, adding to public concern and fuelling newspaper headlines about the annual “NHS winter crisis”.

“Most years you see a spike in the issues tracker for the NHS in the winter months as you get stories about winter crisis, waiting times going up,” said Chris Curtis, Political Research Manager at polling firm YouGov.

YouGov’s latest research showed 32 percent of voters viewed Labour as best able to handle the NHS, versus 26 percent for the Conservatives. In contrast, just 9 percent believed Labour was best on Brexit, compared to 24 percent for the Conservatives.

“It is much better for Labour to be focusing on the NHS than it is for them to be focusing on Brexit,” said Curtis. “It is very likely that that could end up helping Labour in this campaign.”

Many opinion polls give Johnson’s Conservatives a double digit lead over Labour, but it is early days in a six-week campaign.

At the last snap election, in 2017, Johnson’s predecessor Theresa May saw her party’s large poll lead all but evaporate during the campaign, ultimately losing her small majority in parliament on election day.

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