New Delhi, July 27: Niranjan Shah has had lunch with former US President Ronald Reagan and has photographs with Bill and Hillary Clinton from when they occupied the White House in the 1990s.

By September 2014, when he joined Narendra Modi at US Vice-President Joe Biden's lunch during the Indian leader's first visit to Washington as Prime Minister, the 71-year-old Indian American businessman had donated more than $147,000 to Democratic Party campaigns.

But days after Modi left, the Democratic National Convention (DNC), the party's organisation, refused to invite Shah to a dinner US President Barack Obama hosted in Chicago on October 22 that year, citing allegations of corruption and nepotism against him dating back to 2009.

It wasn't a one-off rebuff. From 2009 till as late as this summer, the DNC barred invitations to Shah for any event it hosted that Obama or Biden attended, careful to avoid any photos where the Indian-origin Chicago resident could squeeze in with the President or Vice President.

"Still fails," Bobby Schmuck, a DNC official, wrote in an email on March 14, 2014, to colleagues from the finance wing of the organisation who had sent a fresh request to let "Shah attend, donate, and get a photo with POTUS at the Chicago roundtable in April."

"POTUS" stands for "President of the US".

The exchange between Schmuck and his colleagues was one of over 19,000 leaked emails from the DNC that the whistleblower site Wikileaks made public just as the Democratic Party prepared to meet in Philadelphia to formally pick Hillary Clinton as its presidential nominee.

The emails cast a shadow on the convention, held on Tuesday night, because several of them suggest that the DNC tried to undercut the campaign of Hillary's rival, Vermont Senator Bernie Sanders.

But some of the emails also reveal that prominent members of the Indian American community used massive donations to try and gain access to Obama and Biden, showcasing in some instances their growing influence on American politics and, in other cases like Shah's, their limitations.

"Some people at the DNC have stopped me from events," Shah told The Telegraph from his home in Chicago over the phone on Tuesday.

"It's not my place to comment on the DNC but none of the allegations against me have been established, and my record is absolutely clean."

Like Shah, many of the Indian Americans detailed as donors in the emails have had relations with the DNC and Democratic leaders for years.

San Francisco-based Democratic Party activist Shefali Razdan Duggal, 44, was appointed by Obama in 2014 as a member of the US Holocaust Memorial Council, which oversees the US government's commemoration of the Holocaust and its victims.

On October 30 last year, Duggal wrote to DNC official Eric Stowe to check "how close" her donations to the party were to $1.25 million, a sum that would make her eligible for the top package of benefits during the Philadelphia convention. Stowe replied that her donations count stood at $679,650.

Duggal also politely asked - "not to be a lurker or presumptuous in any way," she clarified in her email -whether she would be invited to a small White House party in November, a larger one hosted by Obama in December, and a party thrown by Biden.

"Should I be invited to the Vice-President's small party in December, I was hopeful to bring both my children, if they have room," Duggal wrote. "Thus, a kind request of one extra ticket? Please? :-)"

Duggal told this newspaper by email that she was "unable to speak this week".

Ophthalmologist Sreedhar Potarazu, who has testicular cancer, had cited his illness as he tried to gain a meeting with Obama, in particular a seat next to the President at a May 2016 roundtable, according to an email exchange between senior DNC officials.

The choice for the seat was between Potarazu and Philip Munger, son of Charles Munger Sr, the owner of multinational conglomerate Berkshire Hathaway.

"The Potarazu family has written $332,250 to us since '13," DNC official Alexandra Shapiro wrote to the organisation's national finance director, Jordan Kaplan, on May 17.

"Munger has written $100,600 (and that's only if you reach back to 2008). I also don't understand why everyone seems to hate Sreedhar so much."

Kaplan's reply referred to Potarazu as Shapiro's "boy".

"He has 'overstepped' his boundaries with Joe and Bobby," Kaplan wrote, referring to two other colleagues. "He has, unbeknownst to us, emailed Joe and Bobby weekly asking to come and see POTUS. Explain about his cancer (sic)."

Potarazu did not respond to an email, and a relative at his home in Greenbelt, Maryland, said over the phone that he would call back if he wished to.

It is unclear whether Potarazu made it to the invitations, but some emails suggest he did not. Joe Paulsen, Obama's special assistant and frequent golfing partner who was referred to by Kaplan in his email, asked the DNC finance director to share his email with Potarazu on May 9.

"Will you give him my email to set up golf at some point?" Paulsen asked.

It's unfair, said Sunita Leeds, a member of the DNC executive committee who too is named in the leaked emails, to characterise the Indian American donor generally as a "puppy dog you need to just pat on the head for more".

Many young Indian Americans are running for public office in the US, and some are involved in grassroots movements, she said. But for older Indian Americans, donations are a route to access that gives them a chance to articulate the community's concerns to political leaders.

"And when you make donations, you have expectations -- like, say, a photo with Bill Clinton," Leeds told this newspaper over the phone from Philadelphia, where she was a super-delegate backing Hillary.

"That becomes a thing of pride. Donations get you in the door."

But that door can also slam shut overnight.

Shah, the Chicago businessman, claimed he had known Obama since 1992, when they were both involved in Bill Clinton's campaign.

According to Shah - a recipient of the Gujarat Gaurav award in 2005, when Modi was chief minister, and of a Pravasi Samman award from the Manmohan Singh administration in 2006 - Obama and he had met for lunch at least once a year since 1992.

"Sometimes, we met twice a year," he said.

But that stopped, he said, when Obama entered the White House. A year later, Shah - a member of the board of trustees of the University of Illinois - was accused of using his position to favour his friends and family. He was accused of recommending his future son-in-law for a job. Shah resigned.

His firm, Globetrotters Engineering, was accused of receiving benefits from the office of then Illinois governor Rod Blagojevich, who was arrested on the charge of seeking bribes in exchange for government contracts.

Shah said that none of the charges against him had been proved. But, the DNC emails show, the allegations continue to haunt him.

"That's the way life goes," Shah said. "There are times when there is nothing you can do."