According to a summary of event packages obtained by POLITICO, which the convention planners circulated at the meeting with lobbyists, the perks for a a $300,000 donation include access to two well-located hotel rooms. The price is steep even by the expensive standard of national party conventions: In 2016, a $200,000 donation included five hotel rooms at the Democratic National Convention in Philadelphia.

But Milwaukee was never chosen as the convention site because it was a Washington party favorite. Done right, the Midwestern convention will help Democrats’ image on a national stage. Past conventions have boosted local parties in the host region, and Wisconsin will be one of 2020’s most important battleground states.

Solmonese has been on an extensive closed-door tour of Washington and Milwaukee to discuss the event and win over skeptics. Last week, representatives from roughly half of all state party delegations visited Milwaukee to begin making plans with their hotels for the convention.

“Most people find Milwaukee to be an inspired and compelling decision,” Solmonese said in an interview. He added: “There no doubt are going to be, as there are with every convention, additional logistical and operational challenges. We’ll meet them and we’ll make sure there is a seamlessness to this convention that people will expect.”

The DNC has not released information on its fundraising goals for the event, which needs $70 million overall. The DNC is on “pace to raise what we need to raise” for the convention and is meeting its other targets, Solmonese said.

Asked what the DNC would do if the Democratic nominee asked for corporate donations to be returned, Solmonese said the DNC has to get the convention "appropriately funded and get it paid for well in advance,” which means accepting corporate PAC donations.

The DNC doesn’t plan to return any corporate money that is donated to the convention regardless of the nominee, convention CEO Joe Solmonese told POLITICO. | Frederick M. Brown/Getty Images

“We can’t know and try to, nor can I ever suggest that we ever try to, bend this towards any one candidate’s philosophy,” Solmonese said.

Solmonese and Sam Cornale, the DNC’s deputy chief executive, held briefings recently at six prominent lobbying firms, during which they updated lobbyists on convention planning and told them how their corporate clients can obtain packages with convention access in exchange for donations to the DNC. They discussed the possibility the Democratic nominee might call on the DNC to reject corporate cash during a briefing at Brownstein Hyatt Farber Schreck, according to a lobbyist present.

David Jones, a longtime Democratic fundraiser who attended a briefing last week at his employer, Capitol Counsel, said the DNC seemed "to be way ahead of the curve” in its planning.

But other Washington operatives said they hadn’t donated to the convention yet because the DNC has been too vague and too slow to explain the convention perks of a donation.

“No. 1, Milwaukee is not as big a city as Philadelphia, and two, the process has been slow. It’s been hard to figure out what we would get for our investment,” said one operative employed by an organization that has contributed to DNC conventions in the past but has not yet given money this cycle.

While Democrats are locked in a slow-moving primary, the convention planners want to encourage donors to give early: Donors must contribute in 2019 and 2020 in order to meet the requirements for getting convention packages, according to the fundraising summary, and contributors who give their 2020 contribution before March 31 will be given “preferred booking” for the event.

The most expensive — “Kilborn Avenue Package” — for instance, includes early access to booking two hotel rooms in the DNC’s block of rooms, VIP convention credentials, box seats, 10 tickets to convention events and other perks. The cost: $300,000.

Union delegations — historically among the conventions biggest funders — face another dilemma when it comes to staying in Milwaukee. While labor unions usually stay in unionized hotels when they travel, there are only four union hotels in Milwaukee. One of those four hotels, Knickerbocker on the Lake, is a boutique hotel with only 60 rooms.

Democrats picked The Fiserv Forum in Milwaukee to host their 2020 national convention. | Carrie Antlfinger/AP Photo

One draft of the convention agreement makes clear how critical labor funding will be to the event: In the draft, labor unions were expected to donate close to $10 million of the $70 million fundraising goal, the Milwaukee Journal Sentinel reported. The final agreement is not public.

“Our priority is to always stay in a unionized hotel,” AFL-CIO spokesman Gonzalo Salvador said.

It’s not the first time the politics of unionization has complicated convention planning. Democrats’ choice of Charlotte, N.C., to host their 2012 convention prompted fury from unions upset about North Carolina’s "right-to-work" laws and unionization rates, which are among the lowest in the country.

Unions toned down their participation in Charlotte, sending skeleton staff and skipping out on sponsoring parties and lunches for members. The Laborers' International Union of North America did not contribute any money after donating $1.5 million to the convention in 2008.

With space in Milwaukee at a premium, the DNC announced in August that 26 state delegations will stay in Northern Illinois during the convention, with some hotel rooms located near O’Hare International Airport — a 90-minute drive without traffic.

Steve Elmendorf, a Democratic lobbyist at Subject Matter, which hosted one of the briefings last week, said he wasn’t concerned by the lack of hotel rooms in Milwaukee.

“Other than New York or Chicago, every other place you go, that’s a question,” he said.

One group that will be housed close to the convention site in Milwaukee, however, is the Republican National Committee. The RNC scouted dozens of hotels near all three finalist cities for the Democratic convention and secured a block of hotel rooms 20 minutes from the convention site before Milwaukee was announced as the host, RNC spokesman Michael Ahrens said. Ahrens declined to say where the GOP hub will be.

Gilberto Hinojosa, chairman of the Texas Democratic Party, said he’s eagerly awaiting announcements about space in the arena at the nominating convention. But Hinojosa said the DNC has been in frequent communication with him and other state party officials about the convention, and he was not miffed to find out his delegation would be commuting at least an hour each day.

“We’ll make sure our delegates get some margaritas on the way up or back — or both — if it’s legal,” Hinojosa said.

Ian Kullgren contributed to this report.