Idaho is about 2.7 times bigger than Maine.

Maine is approximately 79,931 sq km, while Idaho is approximately 214,314 sq km, making Idaho 168% larger than Maine. Meanwhile, the population of Maine is ~1.3 million people (239,221 more people live in Idaho).
Tip: This to-scale comparison of Maine vs. Idaho uses the Mercator projection, which distorts the size of regions near the poles.