Definitely, Maybe (2008) on Netflix

Plot summary

Maya Hayes, 10, comes home from her first sex education class in New York City and demands to hear how her parents met. Her father, Will, an advertising executive in the middle of a divorce from Sarah, agrees to tell the story, but changes the names so that Maya has to work out which woman is her mother. His account begins in 1992, when he leaves Madison, Wisconsin and his college girlfriend Emily to work on Bill Clinton's presidential campaign in New York. There he meets April, a fellow campaign staffer, and Summer, a friend of Emily's. Over the years the three women come back into his life and leave it again, and Maya keeps changing her mind about which of them she wants as her mother.