Just wondering

It's not a popularity contest, it's a "Get the best multiplier" contest, so while more could like Ephraim, Lyon could easily take the lead because of multipliers.

One word!
"MULTIPLIER"

Usually, then team that gets the final multiplier(s)--the 7x or higher-- wins the round because its score gets super inflated. Lyon ended up getting lucky with the multipliers and ended up out-scoring Ephraim despite having less supporters. (A similar thing happened with Marth and Hardin, where Hardin ended up getting both the 7.4x and 7.5x multipliers and won out despite having a smaller army.)

If final battles result in a "Same Hell", then the round essential becomes a popularity contest, and the team with the greater number of supporters would win.

Multipliers were the difference; he got the last 2 and ended up coasting to the victory. He also had notably less support and still managed to win. But now it looks like L!Ike has over 4 times the support Lyon has, so this round is not going to be easy for Lyon supporters.

Do not understimate Lyon popularity. He is a really loved character in Fire Emblem Sacred Stones.

I supported him, and though he would be eliminated against Ephraim (then, I would support Ephraim).

Next one: Ike. This will be hard, but hope luck helps me again.
My supported hero always wins I dunno how or why. Gunntrha was a great example in the last Gauntlet.