WASHINGTON — Congressional negotiators on Monday pressed to wrap up a must-do spending bill to prevent an election-season government shutdown and finally provide money to battle the Zika virus, but numerous sticking points remain and top Senate leaders again postponed a planned procedural vote.

The stopgap measure would keep the government running past the end of the budget year this month. It’s the only measure that has to pass before Congress adjourns for Election Day. As such, the talks have been tricky, with Republicans controlling Congress battling Democrats and the Obama administration.

A controversy involving whether Planned Parenthood should be eligible for anti-Zika funding in Puerto Rico — which sparked a Democratic blockade of an earlier measure — was defused with last week. Senate Republicans, who have taken the lead in the talks, relented and would make affiliates of Planned Parenthood eligible for funds to fight the virus in Puerto Rico.

But unrelated controversies over pesticide regulations, spending cuts and limitations on how many hours long-haul truckers can drive remain unresolved. A request by Democrats to add money to help the city of Flint, Mich., fix its lead-tainted water system is being opposed by Republicans who want it to advance on a separate water projects measure.

Republican Sen. Ted Cruz is pushing for a provision in the bill to ensure that the U.S. government doesn’t relinquish control of the internet’s addressing system. The government is expected to take that step, and Cruz has been fighting it.

“It is my hope that Congress is going to act to maintain current law and to protect the internet, keep the internet free,” Cruz told reporters. “It would be profoundly harmful to American interests and to the free-speech rights of Americans to give Russia and China and Iran greater control over the internet, and I hope we see a bipartisan consensus to protect free speech online.”

After talks over the weekend failed to produce much progress, Senate Majority Leader Mitch McConnell, R-Ky., postponed a procedural vote that had been slated for Monday evening. The delay probably means Congress won’t wrap up its pre-Election Day session this week. The move followed an earlier delay after talks slowed last week.

“I’m encouraged by the headway we’ve made,” said Senate Minority Leader Harry Reid, D-Nev. “There’s still work to be done.” Republicans like Majority Whip John Cornyn of Texas, however, said Reid was showing little urgency to wrap up the talks. Republicans are generally more eager to adjourn for the campaign to defend their endangered Senate majority.

The $1 billion-plus to fight the mosquito-borne Zika virus is months overdue. Republicans were slow to act on Obama’s February request and then sparked an imbroglio with Democrats by restricting new health grants for Puerto Rico to entities like public health providers and hospitals.

Another proposal would temporarily ease pesticide spraying rules from Clean Water Act requirements for permits. but the idea is opposed by the administration, which says it’s an assault on environmental laws.

Democrats also are opposed to pairing the Zika money with spending cuts intended to try to pay for it.