Mr Craig conceded the resignation of his press secretary Rachel MacGregor on Thursday may have lost the party crucial votes.
"Inevitably everything matters. But I don't know. We campaigned very well, the polls were going up for us. We underperformed tonight on the polls, and that is surprising, we have never done that before. So we will ask ourselves why that is."
Asked if this campaign would change how National viewed his party, Mr Craig said that "will be an interesting question".
"It may well do. National have the luxury tonight of pulling in a very big vote, so I'm not sure what their thinking will be. But certainly I think what we have demonstrated... is we do know how to get support."
Read more of the Herald's election coverage here:
• National win three more years with resounding win
• Cunliffe vows to stay on as Labour leader
• John Armstrong: Utter triumph for John Key
• Kim Dotcom says he 'poisoned' Internet-Mana
• Winston Peters hits out at National after big poll surge
• Green leaders in defiant mood despite results
• Colin Craig 'happy' to have improved vote
• As it happened: New Zealand election 2014
The Conservatives gained around 4.12 percent of the vote but no seats because they fell short of the 5 percent threshold. Act, on the other hand, are in Parliament after polling just 0.69 percent of the vote because they won the Epsom seat.
Mr Craig said he would campaign again in East Coast Bays and wanted to win the seat next election. He has previously said he expects incumbent Murray McCully to step down after this term.
Supporters had already expressed their willingness to contribute for another crack at parliament.
Mr Craig said he wanted Conservative voters to know their vote had not been wasted.
"A true wasted vote is when you vote for someone who you don't actually agree with and who is going to do things you don't want, and I think all our voters know that.
"Christine Rankin told the Herald the party was still "a baby" at three years old."2017 is not that far away, and I'll be standing right beside Colin, he is a great man and the country needs him."
Ms Rankin said some supporters would feel like their vote had been wasted, but in reality crucial momentum had been gained.
"You have got to support the up and coming parties who have the right things to offer this country. And we do.
"She said National were probably disappointed that they had let the Conservative vote go to waste.
"But that's part of the game too, isn't it. They had to make the decision at the time, they did, and we have always wanted to get there on our own merits. That's what brings respect."
They are currently polling just below the 5 percent threshold to get into Parliament.
Asked what went wrong, he said they had kept building their vote throughout the campaign.
"I don't know if it's gone wrong anywhere. We'll think about that...it's always been a long-term game. We are not even three years old yet as a party."
Mr Craig said it was a "tough system" to get as many votes as the Conservative Party was likely to receive and not enter parliament.
Asked if he had the resources for another tilt, he said he had three years to work hard and save.
"What we have done is build our membership and our supporter base. It's now getting towards 8500 and that's very strong."
And he fired a shot at "backside handshakes" with National in Epsom and Ohariu."Even though we're the fifth highest polling party, we still won't have an MP ... That's just the system we work with."
