Senate Democrats are staking out their positions on a bill to temporarily fund the government, known as a continuing resolution (CR), which would avert a federal shutdown.

The top Senate Democrat said his members were not ready to provide the votes to allow the Republican-written stopgap spending measure to pass ahead of a March 14 midnight deadline.

Senate Democrats said they do not have the votes to advance a six-month Republican bill to fund the government, potentially increasing the odds of a shutdown when funding lapses on Friday. “Funding ...