The Hammers are currently second from bottom of the Premier League table with 11 games remaining.
The West Ham co-owner told The Guardian: “We’ve got a tough run-in. But we’ve underperformed all season and we’re now paying the price.
“I think, being realistic, (the chance of surviving) is less than 50-50. I actually think a lot of the fans are almost accepting we’re going to be relegated. That’s the case with the supporters I speak to, unfortunately.
“I say to people we’re a long way from being relegated, but we have to do better. It’s going to be a huge, huge struggle.
“But strange things happen in football. West Brom were 25-1 on to be relegated one year and got out of it and Fulham were almost gone one year (and survived).”
“We have got a decent team at the moment, probably the best team we’ve had all season,” he added.
“(Recent signing Demba) Ba is a good striker, (Robbie) Keane is injured, unfortunately, but Thomas (Hitzlsperger) will make a huge difference.
“If he had scored five or six long-distance goals up until now, which he would have done if he had been playing, we would be in a completely different position.”