Raghupati Raghav Raja Ram is a Ramdhun, a repeated invocation of the name of Rama rather than a narrative bhajan. The opening lines address him through his lineage: Raghupati and Raghav both mark him as of the house of Raghu, and Raja Ram names him as king.
The verse most often quoted is Patita pavana Sita Ram — the purifier of the fallen. The devotional claim in that line is that the name is available to anyone, without qualification of birth or standing, and it is what carried the song beyond temple use.
The dhun is traditionally attributed to Lakshmanacharya, and the melody now sung almost everywhere was set by the musician Vishnu Digambar Paluskar. It became widely known in the twentieth century through Mahatma Gandhi, who had it sung at prayer meetings and on the Dandi March of 1930. A verse invoking both Ishwar and Allah is commonly sung with it; that verse is a later addition rather than part of the original dhun, and devotees differ on whether to include it.
It remains among the most recognised devotional songs in India, sung at prayer gatherings, on Ram Navami, and during processions.