Singer Nicole Scherzinger is "hoping" for a reunion with her ex-boyfriend, Formula One racing driver Lewis Hamilton.

The "Poison" hitmaker is desperate for Hamilton to come "running back" to her and she let her emotions get the better of her on her 37th birthday (that falls on June 29) with friends, reports femalefirst.co.uk.

"Nicole was determined to go wild for her birthday and spent most of the day drinking cocktails and champagne, even though her pals warned her to slow down,` a source was quoted as saying by closeronline.co.uk.

"But she received a birthday message from Hamilton at the end of the night, as well as an Instagram post, which made her feel incredibly emotional. Deep down she still loves him and had been hoping that he'd come running back and finally commit,` added the source.

In the sweet birthday tribute, the 30-year-old Formula One star said, Nicole, 37, "made him the man" he is now.