Nebraska is about 1.6 times smaller than New Mexico.

New Mexico is approximately 314,310 sq km, while Nebraska is approximately 199,099 sq km, making Nebraska 63.34% the size of New Mexico. Meanwhile, the population of New Mexico is ~2.1 million people (232,838 fewer people live in Nebraska).
Tip: This to-scale comparison of New Mexico vs. Nebraska uses the Mercator projection, which distorts the size of regions near the poles.