Andy Burnham's barnstorming speech setting out how Labour would better support the NHS went down a storm, with the audience twice springing up to give him a standing ovation.
Shadow home secretary Yvette Cooper's speech to activists this afternoon also went down well, leaving Labour leader Ed Miliband with two of his own shadow cabinet colleagues rising as potential successors.
In his keynote address, the shadow health secretary told activists in Manchester that the next general election would be a "day of reckoning on the NHS" for David Cameron and Nick Clegg.
"A reckoning for trashing the public's most prized asset without their permission," he went on. "And a reckoning for the ruinous reorganisation that has dragged it down and left it on the brink."
Burnham's speech went down so well that bookies have placed him as second favourite to succeed Ed Miliband as Labour leader, with Ladbrokes giving him odds of 7/1, just behind Cooper.
The two Labour frontbencher's stellar performances come just hours after one Labour activist was overheard saying on at the conference: "Get ready for the Andy Burnham-Yvette Cooper dream ticket".
Ed Miliband's Burnham's performance will be doubly awkward Cooper also performed well, with commentators praising her "very impressive" speech this afternoon to activists.
A Survation survey carried out for The Huffington Post found that 55% of voters thought someone else would make a better Labour leader than Ed Miliband, with only 24% believing he was the best leader.
Labour voters viewed Miliband's brother David as by far the most popular replacement when presented with a list of leading contenders. Of those asked, 31% of Labour supporters backed David, while 11% supported Cooper.
Labour supporters quickly captured Burnham's most passionate moments in online "memes", as the Labour frontbencher promised to repeal the coalition's "toxic" NHS reforms.
"The public NHS - protected with Labour," Burnham told members. "Not for sale, not now, not ever."
Mr Burnham said Labour would offer better support to the terminally ill, making it easier for them to die at home if they want to.
He told delegates: "A national health and care service truly there from cradle to grave - from a new right to have a home-birth and a right to be in your own home at the end of your life, surrounded by the people you love, with your care provided on the NHS and no worry about its cost - starting with those who are terminally ill with the greatest care needs.
"These are the things that matter and this is about an NHS there for you at the most important moments in life."
Burnham said he had made it his personal mission to rebuild the NHS a decade ago, revealing a personal story from his own family's history of seeing his grandmother's knuckle left red raw when a care home worker stole her engagement ring.
Burnham said: "She was in a nursing home where corners were often cut and where it was hard to get GPs to visit. The decent people who worked there were let down by the anonymous owners who filled it with untrained, temporary staff.
"My gran's things often went missing and we had got used to that but I will never forget the day when we walked in to see her and her knuckle was red raw where her engagement ring had been ripped off.
"Right there, right then - I made it my mission to end this scandal."
He told activists that only Labour could be trusted to complete the service built by Nye Bevan.
He said: "My message is simple: Labour is with you; your worries are ours; we know things can be better than they are; we want an NHS that takes your worries away; and we can achieve it if we do something bold.
"That allows us to rebuild our NHS around you and your family, no longer ringing the council for this, the NHS for that.
"But one service, one team, one person to call. An NHS for the whole person, an NHS for carers, an NHS personal to you. At last, a National Health Service keeping you well, not a national sickness service picking up the pieces.
"And an end, once and for all, to the scandal that is care of older and vulnerable people in England in 2014."