Last month, Mr Patil's Lok Bharti Party merged with the JD-U, paving the way for the latter to set up base in Maharashtra after Uttar Pradesh, Jharkhand, Gujarat, Karnataka and Kerala.
Post-merger, Mr Patil and other key JD-U leaders undertook a tour of Maharashtra from April 10, conducted meetings with social workers, independent or party-affiliated political leaders, and labour and union leaders.
"Several prominent persons and organisations have decided to back Nitish Kumar's leadership, including some prominent banking unions, affiliates and the Brihanmumbai Municipal Corporation Mazdoor Union, the BEST Kamgar Union, the Mumbai Autorickshaw and Taximen's Union," Mr Patil told IANS.
He said the JD-U's expansion is against the backdrop to project the 66-year-old Bihar Chief Minister as prime ministerial candidate in the 2019 Lok Sabha elections.
Besides Bihar, JD-U claims strong grass-roots and organisational presence in Uttar Pradesh, Jharkhand, Gujarat, Karnataka and Kerala.
Other prominent parties that have since set up base in Maharashtra include the Samajwadi Party and Bahujan Samaj Party of Uttar Pradesh and All India Majlis-e-Ittehad-ul Muslimeen.
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