It is most unlikely that a Romney presidency would have reversed those changes. But further progress - such as a New Zealand port visit by an unquestionably non-nuclear American naval vessel - would have been much less in prospect than it might be under Obama.
Had Romney won, there would have been a forced hiatus in the relationship while the new President conducted a clean-out and his appointees awaited congressional approval before taking up their new roles.
The continuity assured by Obama's victory is important to New Zealand for other reasons.
First, the pressure is now squarely on the President to get the American economy growing again. That can only be good news for New Zealand exporters.
Second, the emphasis on the economy is a major factor in Obama's enthusiasm for a high-quality free trade arrangement in parts of Asia and the Pacific Rim through the Trans Pacific Partnership (TPP).
In turn, the TPP is seen by National and Labour as a back-door means to score a de facto free trade agreement with Washington.
A Romney victory would have likely caused further delay in the already-protracted negotiations.
Obama can now press for a deal without having to worry so much about being punished by a potential domestic protectionist backlash.