David Burrowes was speaking after Mr Goldsmith, the MP for Richmond Park and North Kingston, won 70% of the online ballot to be Conservative mayoral candidate for London in the election next year. He gained more votes than all three of his contemporaries put together.
Zac Goldsmith, 40, is the son of a billionaire and went to Eton. He is a committed environmental and human rights campaigner, and has opposed a third runway at Heathrow Airport.
Mr Goldsmith famously paid £60,000 to conduct a private ballot in his constituency, to see whether they were happy for him to stand as mayor. He vowed not to stand if they voted down his mayoral, but they overwhelmingly voted in favour of it.
He said he was "honoured" to be selected to stand for the Conservatives in 2016.
However Mr Burrowes, the MP for Enfield Southgate admitted that the doing an internet vote to elect the Conservative's mayoral candidate "isn't secure", saying he was "a sceptic but it was good enough".
Some had raised questions about doing an online ballot because of security issues, similar to concerns raised when Labour leader Jeremy Corbyn was elected.
It was also labelled hypocritical by some, given that the government's Trade Union Bill is trying to outlaw trade unions from using the internet as opposed to physical voting to ballot members.
David Burrowes told Premier's News Hour: "He's someone who's passionate about causes, and I think he has a reach that goes beyond party.
"I must admit I had my doubts about the processes because it isn't secure... I'm a sceptic but it was good enough."
Listen to Premier's Aaron speaking to David Burrowes MP here: