Team USA's Kaillie Humphries and Elana Meyers Taylor win Olympic gold and silver in women's monobob

Kaillie Humphries crossed the finish line, jumped from her sled and hoisted an American flag that someone had just handed her into the frosty air.

"U-S-A! U-S-A!" she chanted.

Four years ago, nobody would have seen that coming. The former Canadian bobsled heroine is an Olympic gold medalist for the third time - and for the first time, as a U.S. citizen.