Santara Devi (25) and her daughters were going home after attending a marriage function and the car knocked them down last night, they said.
While the woman and her elder daughter died on the spot, the two-year-old was rushed to Sikar Government hospital where her condition is stated to be serious, they said.
The car's driver fled the scene after the accident, they said.
The bodies were handed over to the victims' relatives after post mortem this morning, they added.