Illinois Attorney General Lisa Madigan’s announcement that she is no longer running for reelection remade the landscape of Illinois politics, drawing a dozen, if not dozens, of potential candidates for the open seat race. But the cost and logistical challenge of mounting a statewide campaign in time for the March 20 primary is what will really limit the pool of serious candidates.

I have some experience putting together an attorney general campaign. In 2009, then-State Rep. Julie Hamos (D-Evanston) hired me to build a statewide campaign operation for the 2010 primary. Lisa Madigan, who was still attorney general back then, announced her intention to run for governor in 2010. She subsequently built a large fundraising campaign and asked pols from across the state to commit to her campaign. Mirroring Madigan’s operation, I helped then-Rep. Hamos criss-cross the state, attend Democratic county chair barbeques and make calls to donors.

Then, with little warning, Lisa Madigan announced in mid-July 2009 that she wasn’t running for governor. Hamos, not interested in running against Madigan, folded her attorney general campaign and ran for Congress instead. She lost that campaign, and retired from the General Assembly.

Eliciting deja vú, Madigan ran a similar script in 2013, publically considering a run for governor. That time, State Sen. Kwame Raoul (D-Chicago) began building a campaign operation for attorney general. Then, suddenly, without warning, Lisa Madigan announced that she wasn’t running for governor and prefered remain as attorney general. Raoul, as Hamos did four years before, stood down his campaign. He’s still a state senator.

What I learned, as did Julie Hamos and I’m sure Sen. Raoul as well, is that building an Illinois statewide campaign is a tremendous task. The state is big. You can drive from one end to the other in a day, but if you’re going to do events, you need to work hard to clump them together within a couple hours drive of each one.

You have to raise a ton of money. A competitive primary campaign will cost $3 to $5 million in 2018, consultants told me this week. The attorney general’s office does not have a natural constituency like governor does, so fewer PACs and lobbyists will want to contribute big dollars to A.G. campaigns.

As a result, primary candidates end up depending on a pool of wealthy, issue-driven donors for a large portion of the fundraising. But even before you get to the “big dollar” people, primary candidates need to demonstrate that they can raise the first $1 million or so from their own base–a large group of people who like them enough and their chances to win that will give a primary candidate multiple $5,000 checks.

For Hamos’ 2009 campaign and in Sen. Raoul’s case in 2014, they had the spring and summer months to put together a campaign operation and get to know donor and party leaders.

Whoever runs now, will need to compress months of handshaking and dealmaking into weeks. They will need a fundraiser and a campaign manager that already have donors and party leaders on speed dial. And they will need a base of supporters who will be able to quickly gather 5,000 to 10,000 high quality signatures for their ballot petitions by the December 4 deadline.

This goes for Republicans as well as Democrats.

Yes, Erika Harold, the former 2003 Miss America from Urbana, is the “establishment” GOP candidate. But until today, she was expected to be a sacrificial lamb. Now that it’s an open race, every Republican state legislator and county official who wants to go up the ladder will be eyeing her seat.

The Republican rush to retire from the General Assembly is evidence enough–plenty of people want out. Now who has enough juice to quickly raise $1 million and attract top flight talent in quick order?

DuPage County Chair Dan Cronin and Kane County State’s Attorney Joe McMahon are Republican names that kept coming up yesterday, as well as State Sen. Karen McConnaughay from West Dundee. More are sure to come.

On the Democratic side, because he’s recently been through the drill, Sen. Raoul is expected to announce plans to run. State Rep. Ann Williams from Chicago’s North Side, has expressed interest, as has McHenry County Chair Jack Franks. Cook County Sheriff Tom Dart is a potential candidate, and former CPS CEO Jesse Ruiz refused to rule out a run to me in an email Friday afternoon.

“No one lets the body get cold before the dirt is piled on,” said one person I contacted Friday, who denied interest in running.

Maybe so, but with such a compacted schedule to stand up a campaign and secure crucial support, we could know all the primary candidates before the end of next week.

This article was updated with the correct date of the primary election.