Mr Patterson (47) said there was a "groundswell" of discontent in the electorate.
National this week lost its candidate when embattled MP Todd Barclay quit over allegations he secretly recorded a staff member. He will stay in Parliament until the election. The party is urgently organising another selection contest. With a 14,800 vote majority, National has a formidable hold, no matter who it selects.
Mr Patterson acknowledged winning the seat would be a big ask but he was still hopeful and said his campaign was getting multiple offers of help.
One target was Queenstown, because of the housing crisis and challenges facing ordinary workers in the resort.
Mr Patterson, a Lawrence farmer, opposed the Shanghai Maling-Silver Fern Farms merger, but lost the battle when farmers voted for it. However, he believed people were "rediscovering the power of democracy".
"If they’re not happy with something, the power is there to change that through the ballot box."
Northland was the best New Zealand example of a worldwide phenomenon.
"Look at the action that Northland’s got now [since voting for Winston Peters]. There’s all sorts of activity going on up there because they were prepared to change their vote.
"I’ve still got to prove myself. I’m going to be working pretty hard to make that happen."
In 2014, New Zealand First did not field a candidate in Clutha-Southland but received more than 2100 party votes.
The National Party is expected to announce a selection schedule soon. Party general manager Greg Hamilton said there was enough time to run a full selection process. The party’s constitution says candidates should be selected two months before an election, making July 23 the selection date. Mr Hamilton said the process could take a few weeks longer, but that had happened for various reasons previously and had not been a major issue.
Mr Barclay’s challenger for the seat last year, Simon Flood, is overseas and could not be reached for comment. Earlier this week, he told the Otago Daily Times he wanted to let the process take its course.
