Redknapp insists the decision is a footballing one.
However, he said: "I haven't been to America to watch him play. But it's not like when I was at Bournemouth and we took George Best.
"We're not trying to fill the stadium, are we? You can't get a seat here anyway.
"I just genuinely feel he could come here and do a good job for us.
"When you're looking to hit Crouchy (Peter Crouch), if you're looking for someone to drop a ball on his head from set plays, free-kicks, corners, there's no-one better in the world."
Explaining how he learnt of Beckham's interest, Redknapp said: "He spoke to my son, to Jamie, about it and that's how it all came about.
"He just said, 'I'd like to come back and play and I'd fancy playing for Tottenham, because I like the way they play'."
Despite Beckham's roots being in north London, Spurs reportedly face stiff competition for his signature.
Redknapp joked: "We're 1-100 - he only wants to play for Tottenham ever since he was a young boy. His grandpa was a Spurs supporter. One of us!"