The Conservatives have been boosted ahead of the general election after overall public satisfaction with the NHS increased in 2014, according to the King's Fund.
The health thinktank analysed data from the British Social Attitudes survey and found satisfaction has increased from 60% in 2013 to 65% in 2014.
The research also revealed outright "dissatisfaction" was at an all-time low of 15% last year.
"Public satisfaction with the NHS is high and has risen significantly, despite a year in which the service hit the headlines for financial pressures and difficulties with A&E waiting times," said John Appleby, chief economist at the King's Fund.
"But as well as an actual increase in satisfaction, this may in part reflect a desire among the public to show support for the NHS as an institution."
The study also found that GP services remain the most popular NHS service in terms of satisfaction, with 71% of respondents satisfied in 2014.
Elsewhere, dentistry continued to have lower satisfaction ratings than other NHS services: in 2014, just over half of respondents were satisfied with the service.
Labour supporters' levels of satisfaction with the NHS also jumped 11%, those for Conservative supporters remained roughly the same and Liberal Democrat satisfaction levels increased by 5%.
The figures come after Ed Miliband announced his "10-year plan" for the NHS. The proposal includes pledges for longer home visits by social care workers, 5,000 new home care staff, and new safety checks to identify people at risk of hospitalisation.
"NHS faces its most perilous moment," the Labour leader said. "The future of our NHS is at stake in this general election."
Miliband also pledged to do away with 15-minute home care visits by recruiting more specialist care workers.
Labour has already promised a raft of changes to be made to the NHS if it wins the general election in May.
The main opposition party previously promised to hire 20,000 more nurses and provide cancer tests and results within a week.