NEW DELHI -- Local assembly elections are being held in five Indian states, giving voters the first opportunity to deliver their verdicts on Prime Minister Narendra Modi's performance since his surprise move to ban the country's largest denomination bank notes -- 500 and 1,000 rupee notes -- in November last year.

The elections have been seen as a referendum on his drastic action, which was intended as a direct attack on the country's endemic corruption. The move caused massive confusion and disruption.

But Modi is fighting to win not just public support for his policy agenda but also a nod from a key constituency for his continued leadership.

In the middle of the night on Feb. 26, Modi received a phone call from a senior member of the secretariat of the right-wing Hindu nationalist group Rashtriya Swayamsevak Sangh, the primary support base of Modi's Bharatiya Janata Party.

The caller menacingly told Modi that the RSS's "Chief" was angry at his performance, deeply disappointed at his poor ability to carry out policies and worried about the possibility that his government could gradually lose public support.

Modi appeared to have been a little disquieted by the fact that Mohan Bhagwat, the head of the RSS, had an aide make the call instead of speaking to Modi directly. It was clearly a gesture to signal his discontent with the prime minister.

The next morning, Modi told some of his ministers about the call, according to a source close to RSS.

Political arm

The BJP has long been considered the RSS's political arm. The RSS is seeking to strengthen the BJP's grip on power so as to promote its religious agenda, intended to make Hinduism the country's official culture and religion.

While Modi, who led the BJP to a landslide victory in the 2014 national assembly elections, can hold his own against the RSS, the BJP itself is still under the group's thumb.

People in Uttar Pradesh rush to the site of Modi's election speech as a helicopter carrying the politician flies over them.

But the RSS's choice of timing to convey its displeasure to the prime minister was a little baffling. Modi's standing with the public will become clear on March 11, when the outcomes of the local assembly elections in the five states, including Uttar Pradesh, will be announced.

The real reason behind the RSS's criticism about Modi's inability to implement policies is not any of his actual policy initiatives, such as the introduction of the goods and services tax, the centerpiece of his economic reform agenda.

The right-wing group's beef about Modi is that he and the RSS are failing to give the organization the respect it feels it is its due, according to the RSS source.

Modi, for instance, failed to inform the RSS in advance of his plan to recall the high-value currency bills, the source said. The BJP also decided on its candidates for the local elections without consulting the RSS.

Modi wants to keep a respectful distance from the RSS, which espouses a radical doctrine that is intolerant of other religions. But the RSS is determined to maintain its sway over the Modi government.

Modi and the RSS have been locked in a power struggle, which tends to flare up during election campaigns.

In April last year, when local polls were being held in the states of Assam and Kerala, the RSS demanded that Modi sack Finance Minister Arun Jaitley.

In the ongoing local polls, the BJP is expected to put together a strong showing in Uttar Pradesh, India's most populous state, home to 200 million people.

Committed to the poor

On one day in mid-February, Modi delivered a campaign speech in a field in the Kannauj district in the state, attracting a capacity crowd of some 50,000 supporters.

Modi stressed that his government is not serving the interests of rich people but is committed to helping the poor, provoking the enthusiastic audience to chant his name.

Plastic chairs prepared for the audience were broken to pieces.

The scene that unfolded at the field in Kannauj stood in sharp contrast to his election speech in the state of Kerala in May last year. Tickets to enter the site were distributed in advance, and dressed-up families came to hear his speech in the evening as if attending a concert. People sat properly on prepared chairs, which they used as umbrellas when it began to rain.

A survey of 2,464 Indians conducted last year by Pew Research Center of the U.S. cast an intriguing light on the academic backgrounds of Modi supporters. The ratio of the respondents who expressed a "very favorable" opinion about Modi was 54% among those who had only an elementary school education. But the figure was 64% for people with a secondary school education and 70% for those with a college diploma or higher.

The findings indicate that low-income earners are disillusioned with the Modi government, which, in their eyes, has failed to bring them benefits.

Changing profile

But the profile of his supporters has apparently changed.

A 36-year-old Muslim man who came to hear Modi's speech in Kannauj said he expected Modi to remake the country's society and economy, which he said has not changed in two decades.

Modi's single move to outlaw the high-value bank notes has given him an image as a clean politician firmly committed to his cause, helping him garner votes in areas where his standing has not been very strong.

But there is no telling how this new wave of support for the prime minister will translate into actual election victories.

Modi's speech, delivered at a field, attracted a capacity crowd of 50,000 people.

The BJP currently controls only 10% of the seats of the Uttar Pradesh assembly. BJP President Amit Shah has set a target of winning two thirds of the seats. But the RSS predicts the party will not secure a majority and intends to call on Modi to replace Shah if the party fails to win half the seats.

Winning a majority in the state would mean that the BJP will increase its strength at the upper house of the national assembly by 10% in the next several years. It currently stands at 20%. That is because upper house members are elected by state assemblies.

That would make the BJP, which controls a majority in the lower house, also the largest bloc in the upper house.

More to the point, the results of the election in the most populous state will define, to a large extent, the power balance between Modi and the RSS.

The RSS is lobbying to have Shah replaced by Nitin Gadkari, the minister of road transport and highways. Gadkari led the BJP while the party was in opposition and campaigned against the proposal to allow foreign investors to own comprehensive retail businesses in the country.

If the BJP fails to boost significantly its strength in the Uttar Pradesh assembly, causing Modi to lose his power battle with the RSS, his reform agenda, which calls for further easing of the restrictions on foreign investment, could be seriously hampered.

Modi's political fortunes as well as the fate of his reform program will be greatly affected by how the poll in Uttar Pradesh pans out.