Former American Idol third season seventh-place finisher Jennifer Hudson came up a winner at Sunday night's 79th Academy Awards ceremony, winning the best supporting actress Oscar award for her Dreamgirls performance.

"Oh my god... I just have to take this moment in, I can not believe this -- look what god can do," Hudson said as she tearfully accepted the award for her portrayal of powerhouse singer Effie White in director Bill Condon's critically-acclaimed film adaptation of Broadway's Dreamgirls musical. "If my grandmother... I didn't think I was gonna win, but wow, [if] my grandmother was here to see me now."

"She was my biggest inspiration for everything because she was a singer and she had the passion for it but she never had the chance, and that was the thing that pushed me forward to continue but I'm so grateful to have my mother here celebrating with me, my boyfriend, my sisters, and my brothers back home, and then I got two of them here -- thank you all for being here and supporting me."

"I'd also like to thank Bill Condon, our director, who's a genius, [and] oh my god, our unbelievable cast. I'd like to thank the Academy , definitely have to thank god I guess -- again -- I can't believe this. Wow, I don't know what to say but thank you all for helping me keep the faith even when I didn't believe. Thank you and god bless you all. And Jennifer Holliday too!"

The 25-year-old former American Idol 3 finalist beat out fellow nominees Adriana Barraza (Babel), Cate Blanchett (Notes on a Scandal), Abigail Breslin (Little Miss Sunshine) and Rinko Kikuchi (Babel) to win the award.

The Oscar win caps a remarkable awards season run for Hudson, who beat out more than 300 other women -- including Fantasia Barrino, American Idol's third season winner -- for the Dreamgirls role that represents her big-screen debut. In December, she co-won (along with Kikuchi) the National Board of Review's Best Female Breakthrough Performance award for her Dreamgirls role. Earlier this year, she won Golden Globe, Screen Actors Guild, and Broadcast Film Critics Association's Critics' Choice awards for the performance -- making her the heavy favorite to also win the Academy's award.

Prior to the awards ceremony, Hudson had received some words of support from the Fox reality show that gave her start.

"We are rooting for you, and I have a feeling that you are going to win tonight," Idol judge Simon Cowell told Hudson in a pre-taped video message played by Idol host and E! News anchor Ryan Seacrest, who interviewed Hudson as part of E!'s red carpet arrivals coverage.   "What you have done is literally extraordinary -- none of us would have called it, apart from me, who I think I did mention the word 'Oscar' when I first saw you in Chicago.  I think you're going to win and guess what, you deserve it -- love you, lots of love, bye, bye."

"Wow, that was really nice, he made me mess up my makeup already and get to crying," Hudson told Seacrest after watching Cowell's video.

"I've never seen him that heartfelt, have you?" Seacrest joked to Hudson. "No, is he OK?," Hudson joked back.