OLYMPIA — Lawmakers planned to negotiate late into the night Tuesday in pursuit of agreement on a new state budget that would end preparations for an unprecedented government shutdown.

Though leaders of the Democrat-controlled House and Republican-led Senate expressed confidence of success throughout Tuesday, they had not announced a deal by 9 p.m.

“We’re getting really close,” House Speaker Frank Chopp, D-Seattle, said shortly after 5 p.m. standing near a conference room where budget negotiators were gathering.

Earlier in the day Senate Majority Leader Mark Schoesler, R-Ritzville, described the two sides as “incredibly close” and on a trajectory to reach a deal. By mid-afternoon, his confidence amplified, he said, “I can’t say if it will be this afternoon or this evening but we’re all incredibly optimistic.”

If and when an accord is reached, it will need to be written into a bill and passed by each chamber. It must be delivered to Gov. Jay Inslee for him to sign before midnight Friday to prevent any interruption of government operations when the new fiscal year begins Saturday.

If lawmakers fail, it means canceling camping reservations in state parks for the upcoming holiday, suspending mental health treatment and social services, and halting the lottery — to name a few of the immediate effects of a shutdown. Roughly 32,000 state workers will be laid off.

“I am confident that government will not shut down,” said Rep. June Robinson, D-Everett, who is a member of the House Democrats’ budget negotiating team. “There are still some big unresolved issues. But there are not a lot of those. We are not going to let this slip away.”

As of late Tuesday, the House and Senate majorities had not agreed on the precise size of the two-year spending plan. Chopp, Schoesler and Robinson each declined to say what elements of the budget remained unresolved.

Back in April, during the regular session, the House passed a $44.6 billion spending plan and the Senate approved a $43.3 billion blueprint.

Since then, negotiators for the House and the Senate, where a coalition of 24 Republicans and one Democrat comprise the majority, have been unable to reconcile their differences. It’s pushed them into a third extra session and to the precipice of a shutdown, which also nearly occurred in 2013 and 2015.

The major sticking point has been how the state will provide public schools with ample funding as demanded by the state Supreme Court in the McCleary case. It will cost in the neighborhood of $7 billion in the next couple of years, and legislators have wrestled for months on whether to get those dollars from new and higher taxes, as Democrats want, or solely from a hike in the statewide property tax, which Republicans want.

Lawmakers also are crafting new policies to ensure school districts no longer rely on local property tax levies to pay for basic education. That likely will require changes in the amount of the levies and new rules for how those dollars are spent.

“This is a generational problem we are solving in education,” Schoesler said. “Getting it right is really important.”

Education funding and the budget aren’t the only outstanding issues.

Negotiations continued Tuesday on a legislative response to the Supreme Court’s Hirst decision, which rewrote the rules for property owners wanting to drill a well on their land. Representatives of House Democrats, Senate Republicans and the governor’s office met several times in search of agreement.

And until there is one, Senate Republicans refuse to negotiate on a new two-year capital construction budget. That could mean lawmakers will need to vote on a bare-bones capital plan before midnight Friday to keep funds flowing to previously approved projects and grants.

Such a stripped-down budget would contain no new spending. That would put at risk money lawmakers want to use for new behavioral health centers, renovations at the state’s psychiatric hospitals, a new building at Edmonds Community College, a pocket park in Arlington and roughly $1 billion for school construction around the state.

Lawmakers could labor into the weekend to deal with the Hirst case requirements and a capital budget. They can continue to work until July 20, if necessary. That is the last scheduled day of this special session.

David Schumacher, Inslee’s budget director, said there are too many important things in the capital budget for lawmakers to leave town without acting.

“There’s no way we are going to walk away from that,” he said.

Jerry Cornfield: 360-352-8623; jcornfield@heraldnet.com. Twitter: @dospueblos.