Before آپ go flaming on me, I should remind آپ that this is my opinion and since this is the Amuto vs. Tadamu club I should say that this is the most appropriate place to write it down.

1) Ikuto is protective of Amu. Although Tadase is also, I would say that Ikuto is سے طرف کی far مزید protective of Amu than Tadase is (my opinion). Ikuto likes to flirt and tease Amu, much for us شائقین to describe him as "naughty". Amu becomes embarrassed and gets all defensive around Ikuto. But what she doesn't know is that Ikuto does this to cover his strong feelings for her and to protect her from being hurt/killed سے طرف کی Easter. When Ikuto confesses to her, somewhere in episode 74-75 I think, she doesn't believe him and thinks he's just teasing her. But in episode 100, Amu opens her دل to him fully and hugs Ikuto, دکھانا her true feelings towards him and they transform into Amulet Fortune and Seven Seas Treasure.
2) Amu gets upset when Ikuto leaves to find his father. Amu's stubborn side and Tsundere personality come out here. (Manga reference) When Ikuto takes her on a "date" at the abandoned theme park, which he says is the last time he'll see her. Amu is shown to be deeply hurt and calls Ikuto an idiot for leaving (it's obvious she doesn't want him to go) his mother and runs away, crying in fact. The اگلے day, when Ikuto is about to leave, Ikuto confesses that he loves her once again and kisses her near the lips.
3) Amu only liked Tadase for his outer appearance. (Manga reference once again) In Chapter 48, Amu tells Tadase's older self (believing it was Tsukasa) that she only liked Tadase for his outer appearance and not the true Tadase. And that Ikuto was able to "somehow come into her heart". Although she doesn't know if it was "real love" یا not.
4) The cover of Shugo Chara! Encore! is an Amuto one. Following the other chapters, Rihiko, Kuuatu and Kairi and Yaya, so it's obvious that Amuto wins.