"I think that my value is that I'm quite experienced, and that I haven't been around Parliament for 30 years," he said.
"I have a very good understanding of rural and provincial new Zealand and the issues that affect them, and probably have a knowledge that is useful to my party.
"I'm not young, and if Winston [Peters] doesn't get back in I could well be the oldest member of parliament, which is not something I ever planned on."
McKelvie said two of his proposed bills, the Livestock Rustling Bill and the Dog Control Act, had gone through Parliament during his current term.
"I suppose that's a bit of an interesting thing to happen, especially when you're not in government."
When asked about the upcoming euthanasia and marijuana referendums, McKelvie said at present he would be voting "no" to both, although he had "no problem at all" with the use of medicinal marijuana.
"From my perspective I'm certainly opposed to both of them [referendums], and I'm opposed to marijuana based on my experiences of the damage I've seen to people my age who started smoking at a very young age.
"I don't think that the bill they've proposed to introduce deals with my concerns in any way.
"I have some sympathy for the euthanasia bill, and I think if there were some slightly stricter controls around it, I would have been in favour actually."
McKelvie was a farmer for the first 45 years of his life and entered politics after completing a short course at Sydney University, running for Mayor of Manawatū in 2002 before entering the race for the Rangitīkei seat in Parliament in 2011.
"If you compare it to poor old Chester Borrows who stood for nine years before he won Whanganui, I had a pretty breezy run into politics really."
McKelvie said New Zealand had to "grow its way out" of Covid-19 debt, as opposed to "tax its way out of it".
"The only way to grow our way out of it, in my view, is to stimulate the private sector and get them going.
"That doesn't necessarily mean injecting money into them either, it means putting policy in place that will allow them to move quickly.
"The last six months has changed the emphasis New Zealand needs to have on its future, and I think we have a huge opportunity to diversify our productive base.
"We are going to have a lot of people that will need to be redirected, and I think we have to make sure the conditions and pay around our employment sector are good."