If Joe Biden wins the US election, New Zealand could expect a "more conventional presidency", says former New Zealand diplomat and trade deal negotiator Charles Finny.
The Democrat Biden could lead with more predictability and less disruption for New Zealand, Finny said.
It looked like the Republicans would have a majority in the Senate, he said.
"That could mean that Biden won't be able to achieve as much as he wants to achieve," Finny said.
"But the Republicans in the past have been free traders, maybe they will revert to the form they were in before Trump became president and be supportive of a trade agenda that best suits New Zealand.
"There's a lot of uncertainty there still."
Biden had supported the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP), but it was uncertain whether he could get his party to agree to the US joining the trade agreement.
"He would be much more likely to join this agreement than a second Trump presidency," Finny said.
Victoria University professor of strategic studies Robert Ayson said a Biden administration was looking likely and this would change the US "tone" towards international institutions.
"So New Zealand will find in America a partner that is much closer on supporting multilateralism," Ayson said.
"Even though Mr Biden will want to take the US back into the Paris Climate Change Accord, he's going to need the Republicans if he wants to spend some big money on climate change mitigation.
"That's going to be the big issue."
Ayson predicted a "more steady hand" from Biden in the relationship between the US and China.
"China might find there is some room for a little bit more common ground, but they won't be thinking that suddenly they are going to move into a period of détente with the Biden administration," he said.
"The Biden administration is still going to have expectations from partners and allies, who will be treated more steadily, that they will be firm on China, so that challenge for New Zealand doesn't disappear."
Ayson predicted Russia would find a Biden administration "tougher" than Trump's presidency.