CNN  — 

Republican lawmakers are directly urging President Donald Trump on Thursday to sign a bill to avert a government shutdown, underscoring the uncertainty on Capitol Hill in whether Trump is on board just hours before Congress is supposed to vote on the package.

After the prayer to open the Senate, Sen. Chuck Grassley, Republican of Iowa, said, “Let’s all pray that the president will have wisdom to sign the bill so the government doesn’t shut down.”

As lawmakers prepare to rush the bill through both chambers ahead of a Friday night deadline, it was still unclear whether Trump would surprise Capitol Hill again and oppose its bid to keep the government open.

“I pray” Trump signs the bill, said Sen. Richard Shelby, the Republican chairman of the Appropriations committee. He said he spoke with Trump last night and the president was in “good spirits.”

In December, Trump rejected the Senate’s short-term bill to keep several federal government agencies, including the Department of Homeland Security, running through February 8, following through on his threats to shut down the government over his request for billions of dollars to build a wall on the US southern border. That decision led to a 35-day partial government shutdown, the longest in US history. Three weeks ago, Trump conceded to public pressure to temporarily reopen the government and pay about 800,000 government workers.

While the bill is expected to pass the House and Senate on Thursday, some members of Congress have grown frustrated with the process. In the wee hours of Thursday morning, a group of congressional negotiators dropped the spending bill, which is more than a thousand pages. Sixteen out the 17 bipartisan negotiators who helped craft the bill signed on to it, but the 17th – Republican Rep. Tom Graves of Georgia – said on Twitter that even he was not given enough time to review the legislation and would not.

When asked if he’ll support the spending bill, Sen. Tom Cotton, Republican of Arkansas, said, “I’ll let you know when I’m done with all 1,100 pages.”

“We’ve had no process, no ability to amend this, very little ability to even evaluate it,” added Sen. Pat Toomey, Republican of Pennsylvania. “I’m still in the mode of evaluating it – and I haven’t decided yet how I’m going to vote.”

CNN’s Manu Raju and Phil Mattingly contributed to this report.