The Red Knights' attempt to take control of Manchester United looks increasingly doomed to failure after it emerged that key players within the consortium have become disaffected and are losing hope of persuading the Glazer family to relinquish power at Old Trafford.

Senior figures involved with the Red Knights have told the Guardian there are internal divisions and that they suspect they are fighting a losing battle when it comes to putting together a takeover bid of sufficient value to end the Glazers' unpopular regime.

Although the consortium is rigidly maintaining its public stance that it is confident of being in power for the start of next season, one of the businessmen prominently involved has lost confidence to the point that he believes they might not even submit a bid were it not for the criticism they would attract after such a highly publicised campaign. His belief is that, if they did lodge an offer, it would be for "face-saving" purposes, in the knowledge that it would be turned down, and that it would not be followed up with an improved bid. Instead it would lie dormant, with the Red Knights claiming the Glazers were over-pricing the club.

Another high-level source has said the problems arise from bringing together so many different investors, many of whom have contrasting visions for the future, particularly when it comes to the possibility of giving the club's supporters a substantial percentage of the ownership. The Red Knights have made a point of embracing groups such as the Manchester United Supporters' Trust (MUST) but internally there are people involved who believe they have made a mistake leading such an aggressive campaign through the media, publicly criticising the Glazers in the process.

The group of wealthy United-supporting individuals, put together by the investment banker and former Old Trafford director Jim O'Neill, have been operating with a carrot-and-stick approach – the carrot being a bid, probably around £850m, and the stick being a recommendation for season-ticket holders not to renew under the current regime.

The idea was that a mass boycott would put financial pressure on the Glazers and almost bully them into believing they should sever their ties with the club. The Red Knights guaranteed, in turn, that boycotters would eventually get their season tickets price at reduced prices but it has since become clear to O'Neill and his colleagues that there is not enough support for the move and that it would have little impact on the Glazers.

The club says it is relaxed about selling all 55,000 season tickets and filling Old Trafford for every home match next season. "If there's a threat, then we'll see but our season ticket sales and renewals for this upcoming season are on track for previous years," the chief executive, David Gill, said. "Our executive ticket renewals are on track, so we'll have to see at the start of the season, but we're envisaging sell-out crowds going forward for Manchester United."

The Glazers took control at Old Trafford in 2005 and have the backing of the club's manager, Sir Alex Ferguson, but the supporters have been waging a hostile campaign against them, leading to voluble protests at every match.

"It really is incredible but since the Glazers took over they have wasted £437m in fees and interest, more than the total ticket revenue (£398m) for the full five-year period of their ownership," said a MUST spokesman. "Every single penny we've spent on our tickets over their five-year ownership has been wasted. Or to put it another way, every one of us could have attended every match free of charge for the last five years and on top of that the club could have given every season-ticket holder £700 each – and would still have been no worse off."

The Glazers maintain that the club is not for sale and, privately, they have described the Red Knights as "naive". The Florida-based family say they have already turned down several offers, including a £1.5bn bid from the Middle East towards the end of last year. That figure has been disputed by the Red Knights, whose information is that it was £1bn, but their own efforts to put together a bid have been described by one key figure as "looking a bit grim".

In their last public statement the Red Knights admitted the "process [of formalising a bid] is understandably complex and taking time" and that it would be "wrong to offer above fair value".