Can NRI's participate in Indian elections?
Section 20A of the Representation of People Act, 1950 accords voting rights to Indian citizens residing in other countries.
Election Commission of India clarifies that a citizen of India, absent from the country owing to employment, education etc, has not acquired citizenship of any other country and are otherwise eligible to be registered as a voter in the address mentioned in your passport.
Which means "Every citizen of India:
(a) whose name is not included in the electoral roll;
(b) who has not acquired the citizenship of any other country; and
(c) who is absenting from his place of ordinary residence in India owing to his employment, education or otherwise outside India,
is entitled to have his/her name registered in the electoral roll as 'Overseas electors' in the constituency in one’s place of residence in India as mentioned in one’s passport."
All the information on the procedure to register as an overseas voter can be found on https://eci.gov.in/voter/service-overseas-voter/
After getting enrolled in the electoral roll, such person can cast one’s vote in India during Assembly or Parliamentary election at the respective polling station after showing his/her valid Indian passport.