As the race between Donald Trump and Joe Biden hurtles towards a nailbiting finish, political leaders around the world will be facing a nervous wait for results too.
So who does Ardern want to win, and what would another Trump victory mean for her and New Zealand?
University of Waikato Professor of Law Alexander Gillespie told Newshub he thinks on balance he thinks Ardern would like Biden to win.
"Broadly Biden's approach is more in line with what New Zealand is trying to achieve," he says.
"Biden is more multilateral than Trump, New Zealand as a small country needs a rule-based order on a global level."
Gillespie thinks Trump is "ambivalent" towards us - and his primary interest is doing what he sees as in the US' interest.
New Foreign Minister Nanaia Mahuta told Newshub she's "not in a position to comment on the outcome of the American presidential election".
"It's for the American voters to decide what happens in their own country," she said.
"In a day or so we'll know the outcome and then we'll be in a position to continue conversations.
"The most important thing from a foreign affairs international relations point-of-view is that across the world we have got to continue to foster and strengthen our relationships with other countries."
What Ardern would face from Trump on the big issues
"Climate change is one of - if not the biggest issue- facing the international community," Gillespie says.
"The climate will get worse over coming decades so New Zealand trying to get climate change response going."
But Trump has rolled back US efforts to reduce emissions, including exiting from the Paris Agreement.
"Trump's exit from the Paris Agreement was significant for the abandonment of the US's emissions target, but possibly more so for the loss of leadership and financial support needed to encourage sustainability in the developing world," Gillespie writes for The Conversation.
"New Zealand has committed to net-zero carbon emissions by 2050. This goal is shared by Biden, who would also recommit to the Paris Agreement and the WHO."
But on the other hand, Gillespie warns Biden has signalled he's open to using trade agreements to combat global warming - which could impose penalties on our agricultural sector.
The rise of China
New Zealand's foreign policy has faced a balancing act between our traditional ally, the US, and our increasing reliance on China for trade.
Gillespie says international relations in the Pacific is one of those areas where there's not a lot of difference between Trump and Biden.
"Trump went hard on China in the trade war, and if anything Biden may be more hawkish than Trump," he tells Newshub.
"On the China question, Trump might be better for a New Zealand perspective."
Gillespie says New Zealand is heavily dependent on international trade and overall Biden will be better for New Zealand.
"Trump only sees trade in terms of his own country," he says.
"He doesn't like the WTO [World Trade Organisation] and ripped up participation in the TPPA. Biden might reenter the TPPA because he wants to create mechanisms as a counterweight to China, so New Zealand will get a better deal with him. Biden also supports the WTO."
The reelection of Trump would fan the flames of the US culture war to a white heat. Already we've seen this spill over to New Zealand, with controversy over freedom of speech, de-platforming, armed police and the Black Lives Matter marches.
Gillespie doesn't think a Trump reelection will make it more difficult to Ardern to govern in New Zealand, saying the real power over these issues in the US will lie with Congress.
"Just how that body is made up will determine how Americans will deal with the culture wars and at the moment a lot of legislation is in limbo. It will come down to how their Congress is made up."
The last thing to look at is arms control. Trump pulled the US out of the Open Skies Agreement and the Intermediate-Range Nuclear Forces Agreement.
"In that regard, Trump is a disaster for international arms control while Biden might be likely to renew some of those agreements," he says.
"Anything that prevents the international arms control architecture completely collapsing will benefit everyone," he adds in his article for The Conversation.
"For New Zealand, it would mean the nuclear-free foreign policy was once more in step with global goals."