But today's results show Garner is failing to fire with listeners, with his afternoon drive show losing 7,500 listeners since the last survey period.
Garner began hosting Radio Live's drive show in 2012 but has failed to significantly grow his audience in that time. He will now have an even harder struggle ahead, taking on Mike Hosking in the battle of breakfast talk radio.
"We relish and thrive on competition - but we're not daunted by it. These results highlight the power of the Mike Hosking Breakfast Show and Newstalk ZB generally, epitomised by the unrivalled coverage of Donald Trump's election triumph in the past 24 hours. Having Mike and the likes of Barry Soper and Jack Tame on the spot in New York highlights our commitment to quality news and broadcasting," said NZME's managing editor Shayne Currie.
The independent survey, conducted by research company GfK, found more Kiwis are listening to radio than ever before, up more than 38,000 listeners since the last survey.
The upward trend highlights the importance of radio for MediaWorks, as television continues to lose audience.
Meanwhile, NZME's music brands showed strong growth, with ZM, Flava, Coast, Hauraki and Mix all successfully growing audience.
ZM's breakfast show with hosts Fletch, Vaughan and Megan claimed more than 31,000 new listeners to close the gap on key rival The Edge, which lost listeners. ZM now has the fourth biggest breakfast show in New Zealand.
"Fletch, Vaughan and Megan are gaining on The Edge and the path we set out on three years ago is starting to really reap rewards," said NZME group director entertainment Dean Buchanan. "For example, in Auckland, Fletch Vaughan and Megan beat Jay Jay, Dom and Randell in the all important 18-39 market. That's a big win."
Newstalk ZB is owned by NZME, which owns and publishes the New Zealand Herald.