Kirk Wagar, a Florida lawyer who has raised more than $1 million for President Barack Obama’s re-election bid, had his choice of rooms for the Democratic convention at Charlotte’s Ritz-Carlton or Westin hotels and nightly access to hospitality suites off the convention floor.

Jay Snyder, a New York financier who has raised at least $560,000 for Obama, was entitled to get his picture taken on the podium at the Time Warner Cable Arena.

And Azita Raji, a retired investment banker who has raised more than $3 million for Obama — more than almost anyone else during the past two years — could get pretty much anything that she wanted last week in Charlotte: briefings with senior Obama officials, invitations to post-speech parties, along with “priority booking” at the city’s finest hotels.

In the race for cash, Obama often praises his millions of grass-roots donors, those die-hards whose $3 or $10 or $75 contributions are as much a symbol of the president’s political identity as they are a source of ready cash. But his campaign’s big-dollar fundraising has become more dependent than it was four years ago on a smaller number of large-dollar donors and fundraisers.

All told, Obama’s top “bundlers” — people who gather checks from friends and business associates — raised or gave at least $200 million for Obama’s re-election bid and the Democratic National Committee through the end of May, close to half of the total up to that point, according to internal campaign documents obtained by The New York Times.

The documents provide a detailed look into the intricate world of presidential fundraising, which Obama and his team have mastered, and donor-stroking, which some supporters complain they have not. The campaign closely monitors its top bundlers, rating them by how much each individual or couple has raised and donated each year going back to 2007.

Officials used that amount, in turn, to offer donor packages of access and entertainment for the convention last week, themed to the location in North Carolina: “OBX” (bumper-sticker shorthand for the Outer Banks) for those raising at least $1 million, down to “Carolina on My Mind” for those who have donated merely $75,800 to Obama and the Democratic National Committee, the maximum allowed under federal law.

“It confirms everything we’ve always believed about the role of big money in politics,” said Ellen Miller, executive director of the Sunlight Foundation, a watchdog group that tracks political fundraising. “The more you give, the more you gather, the more you get.”

Each individual or couple is also assigned a lifetime Obama total. Topping the list is Jeffrey Katzenberg, the Hollywood producer, who, along with his fundraising partner, Andy Spahn, has brought in at least $6.6 million combined for the 2008 and 2012 campaigns, according to the documents.

The top fundraiser for 2011 and 2012 is Andrew Tobias, a Miami-based author who is treasurer of the Democratic National Committee and a major bundler for Obama among gay donors. Terry McAuliffe, a former party chairman and Bill Clinton loyalist, shot into Obama’s top bundler ranks this year after he and Clinton agreed to hold a Virginia fundraiser for Obama. He has raised about $2.2 million for Obama, according to the documents, more than all but a few supporters.

Because not all of Obama’s bundlers are represented through the end of May, the documents may understate the total that top supporters have raised for Obama. But even so, they reveal how dependent even Obama — whose grass-roots fundraising machine is unrivaled in political history — is on a relative handful of wealthy individuals raising millions of dollars on his behalf, often while having significant business or legal interests before the Obama administration.

Among the top 10 fundraisers on the list for 2012, for example, are Steve Spinner, a former Department of Energy official who pushed the White House to approve a $535 million loan guarantee for Solyndra, the failed solar power company.

DreamWorks Animation, the studio Katzenberg leads, is among several in Hollywood that earlier this year were notified of an investigation into whether entertainment companies had made illegal payments to officials in China in connection with their dealings there.

Mitt Romney has fielded an equally formidable high-dollar fundraising machine this year and could raise as much or more than Obama during the election cycle. Like the Democrats, Republicans offered big donors an array of perks at their convention, held in Tampa, Fla., last month, including choice hotel access, boat trips and access to Romney himself.

Obama already makes public the names of his bundlers, along with ranges for how much they have raised, a practice not required by law. Romney has declined to release such information, although monthly disclosures filed by his campaign suggest that he is even more dependent than Obama on big bundlers and donors who have given the legal maximum.

“Our major volunteer fundraisers, as well as the ranges of contributions they raised, were previously made public because unlike Gov. Romney, we disclose them on our website,” said Ben LaBolt, a spokesman for Obama.

Obama’s publicly disclosed categories stop at the $500,000-and-up level, however. The internal documents show that at least 60 individuals and couples reside in an even more elite club, having raised more than $1 million for Obama and the party.

They include Frank White Jr., a technology entrepreneur who has raised $2.3 million for Obama’s re-election campaign; Anna Wintour, the editor of Vogue, who has raised $2.7 million; Robert Wolf, a former executive at UBS Americas, the banking company, who has raised about $1.3 million; and Reshma Saujani, a hedge fund lawyer and politician active among young larger donors, who has raised about $1 million.

About 260 of the bundlers did not raise any money for Obama during his 2008 campaign, according to the document. That reflects the extraordinary effort that Obama made to recruit new fundraisers for his re-election effort, as former supporters lost enthusiasm or moved on to other pursuits.

But it also reflects the difficulty of incumbent presidents who have rewarded first-term donors with ambassadorial and other posts that prevent them from giving to the candidate’s second-term efforts.