Spurs climbed to 13th in the table with an impressive 4-0 victory over Middlesbrough in midweek and another win at Sunderland on Saturday would take them into the top half.
Redknapp has been pleased with his players since he arrived at White Hart Lane in October following a disastrous start to the season under Juande Ramos, but he is anticipating a hard game against the Black Cats.
He told Sky Sports News: "We've been on a good run and since I've been here we've only lost one home game.
"It is a tough game. Anyone going to the Stadium of Light is going to find it difficult. They have a strong side and it is a great atmosphere there.
"But we are in good form so we go there full of confidence."
Everyone involvedTottenham are currently four points above the relegation zone and Redknapp expects a tight finish in the battle to stay up.
He explained: "You look from Fulham down and everyone is involved in it still. Even Steve Bruce on 35 points will be thinking he needs to win two games and a couple of weeks ago you thought Wigan were out of trouble.
"Anyone can go into freefall because everyone is scrapping and picking up points.
"They are all decent teams down there. Middlesbrough are capable of going on a run, Blackburn are a good side with Sam (Allardyce) there and Stoke are winning.
"I wouldn't like to say what is going to happen. It is going to be so tight come the end of the season that you just have to make sure you pick up the points as quickly as you can."
Tottenham's good form has prompted suggestions that they could go on to finish in the top seven and secure European qualification.
However, Redknapp is not thinking about such matters and is concentrating solely on making sure Spurs avoid the drop.
He said: "I just concentrate on getting the points to get us out of the relegation battle.
"I came here when we had two points from eight games and to make sure we stay in the Premier League is the most important thing.
"Anything above that is going to be a bonus."
No big dealTottenham had an offer for Sunderland striker Kenwyne Jones turned down in the winter transfer window, with Ricky Sbragia criticising the London club for the methods they had used to try and sign him.
But Redknapp insists the relationship between the two clubs is good, adding: "I get on well with (Sunderland chairman) Niall (Quinn) and I think the chairman gets on well with Niall.
"The club made a good bid for Kenwyne Jones and I'm sure Niall was pleased to say to his owners 'we've got a player that a club wants to pay all this money for, what a good piece of business we did when we bought him'.
"They turned the offer down, Kenwyne signed a new contract and we move on. It is no big deal."