Blackburn entertain Portsmouth on Saturday looking to build on a record of only one defeat in nine league games on their own patch.
A victory will surely assure Rovers of Premier League football again next season and Allardyce said: "I would consider us safe if we make it to 40 points. Let's do it with two games to spare.
"It will be a tense, nervous affair. We know that one win wherever can change the whole shape of the table. We have to use all our experience.
"There has been a great turnaround of form at Ewood Park and it could have been even better.
"Four wins, four draws and only one defeat is very good considering where we started from.
"The players look forward to playing at home especially as there has been such a good atmosphere the last few games.
"The key has been our good defensive work. That has given the attacking players a platform to work on to get the goals we need to win a game."
The spotlight will again be on striker Benni McCarthy as Roque Santa Cruz and Jason Roberts remain sidelined through injury.
Roberts looked to be on the verge of a comeback from a stress fracture of the foot but Allardyce has erred on the side of caution.
"We cannot take any chances that the bone might break again," said the Blackburn boss. "We will leave it for now and hopefully he will get a game in before the end of the season."
McCarthy gave Blackburn a scare last weekend when he came off with a knock in the defeat by Manchester City.
However he has shown no ill-effects this week and seems certain to be again partnered up front by Chris Samba.
Allardyce said: "Benni is okay. We did not want him to take any more risks against City, that's all."
McCarthy has been omitted from the South Africa squad for the prestigious Confederatios Cup tournament, which begins in his homeland next month.
Allardyce is quietly pleased about that situation and said: "Benni can now go and spend some time with his family when our season finishes and get himself together.
"From day one of pre-season we will working to get better, fitter and stronger for the Premier League."
Meanwhile on-loan full back Danny Simpson has left Blackburn and returned to Manchester United.
Allardyce said: "Danny wanted to go back and train with them as his first-team appearances here have been limited. We allowed him to do that after he played for the reserves in midweek."