Cambodia is about 1.7 times smaller than New Mexico.

New Mexico is approximately 314,310 sq km, while Cambodia is approximately 181,035 sq km, making Cambodia 57.6% the size of New Mexico. Meanwhile, the population of New Mexico is ~2.1 million people (14.7 million more people live in Cambodia).
Tip: This to-scale comparison of New Mexico vs. Cambodia uses the Mercator projection, which distorts the size of regions near the poles.