Judith Collins on her chances of being leader of the National Party

National MP Judith Collins is "very happy" with her current role in the caucus and is "very happy" to support incumbent leader Todd Muller, the former lawyer revealed on Sunday.

Collins, who is currently ranked fourth in the caucus, has frequently batted off suggestions that she should lead National following positive poll ratings - including an informal poll by The AM Show in April, that found 39 percent of participants wanted her to take over former leader Simon Bridges. 

Despite announcing her intention to replace both John Key and Bill English as leader of the Opposition in both 2016 and 2018 respectively, Collins has yet to take the top job - and she doesn't want it.

Speaking to Sunday Cafe host Roman Travers on Magic Talk, Collins said she's content with her current roles, which include spokesperson for Economic Development, Regional Development and Pike River Re-entry. 

"I think every politician that goes into Parliament likes to hope that their colleagues would think that they could do something. It's a hell of a job. If people wanted me to do it, then they've had a couple of chances to tell me that in the caucus," she told Travers.

"It's not something I'm ever going to go and bust a gut to get to be."

Collins described current Opposition leader Muller - who rolled Bridges in May during an emergency caucus meeting - as "perfectly nice". 

"There's a perfectly nice person in the job now, who I get along very well with and I'm very happy to support," she said.

"I'm there doing whatever the caucus wants me to do - they want me to do what I'm doing, and I'm very happy doing that. 

"I couldn't think of anything more fun than working with people that appreciate me... I'm very happy with what I've got at the moment."

Collins, who can now add 'author' to her list of credentials following the release of her memoir Pull No Punches on Friday, also revealed her stance in the upcoming cannabis referendum. 

"I'm still deciding... I didn't ever use cannabis, but I know medicinal cannabis - I've got no problem with at all. I am concerned about the strength of the cannabis that's apparently available at the moment and what the messages are that it sends," she explained.

"Generally I think I'm probably going to be opposed to it, but I'm still going to think a bit more about it - but I'll most likely be opposed."

She also addressed the 'Crusher Collins' moniker that has dogged her Parliamentary persona, noting that the tag can make her appear "one-dimensional" - however, feeling misunderstood or misrepresented by the media no longer phases the Papakura MP. 

"I don't go home and cry myself to sleep. I'm always grateful that anyone knows who I am... in my business, name recognition is really important," she said.

"A lot of it is around whether or not you get things done and you're ready to put yourself out there. If you're not ready to put yourself out there, you'll probably never be known for anything or even be remembered."

Earlier this week, Collins denied that the resignations of National's former deputy leader Paula Bennett and veteran MP Anne Tolley are indicative of senior caucus members jumping ship ahead of the election, saying she would never give up her electorate unless she was about to leave Parliament.

"Both of them announced some time [ago] that they were giving up their very good electorate seats," Collins said.

"My experience in politics tells me that electoral MPs, like myself and both of them, do not give up their seats unless they're looking to the future and moving out to something else."