Russia spans the entire Asian Continent plus a third of Europe. I'm pretty sure most of the former SSR's and Moscow are considered Eastern Europe, but including Kaliningrad, Russia has 9 time zones (until recently it was 11, but they combined a couple). "Asian people" are generally thought to inhabit the areas to the East and South of Russia and the former SSR's, but Russia itself spans all of them to the north. So when you're talking about the entire geopolitical unit, it's pretty much impossible to call Russia either European or Asian exclusively.
By comparison, the U.S. spans six times zones, but only because of Alaska and Hawaii (actually, 7 time zones if you include American Samoa and Guam). If I recall correctly, on a map you can fit just over two Continental U.S.'s end-to-end in the land mass occupied by Russia. If you combine the Continental U.S. with Alaska (which is more than twice the size of Texas), that's roughly half of Russia's total area.
By comparison, the U.S. spans six times zones, but only because of Alaska and Hawaii (actually, 7 time zones if you include American Samoa and Guam). If I recall correctly, on a map you can fit just over two Continental U.S.'s end-to-end in the land mass occupied by Russia. If you combine the Continental U.S. with Alaska (which is more than twice the size of Texas), that's roughly half of Russia's total area.