House Republicans are slated to vote Tuesday on their spending bill, known as a continuing resolution, that would fund the government at current levels through Sept. 30, 2025.

In the absence of Democratic support, the vote represents a major test for Speaker Mike Johnson — as it remains unclear if the Trump-backed legislation can even pass in the GOP-controlled House.

Johnson needs near-unanimous GOP support and can only afford to lose one Republican before a second defection would defeat the bill if all members are voting and present. Kentucky Rep. Thomas Massie said he will vote against the measure and Georgia Rep. Rich McCormick told reporters he’s also leaning against voting for the bill. Several others are undecided, including Reps. Tony Gonzales, Andy Ogles, Tim Burchett, Cory Mills, Eli Crane and Brian Fitzpatrick.

Johnson projected optimism on the bill’s prospects, saying he’s confident the measure will pass. “I feel good. I think we’ll have the votes,” Johnson told reporters Monday night.

President Donald Trump has played an outsized role this time around — the first shutdown threat of his second term — practically begging Republicans to support the measure. The president even placed phone calls on Monday to some lawmakers who are on the fence in an attempt to shore up the votes, according to a White House official.

“The House and Senate have put together, under the circumstances, a very good funding Bill (“CR”)! All Republicans should vote (Please!) YES next week. Great things are coming for America, and I am asking you all to give us a few months to get us through to September so we can continue to put the Country’s “financial house” in order,” Trump said on Saturday in a post on Truth Social.

Trump added, “Democrats will do anything they can to shut down our Government.”

Across the aisle, Democratic leaders are urging their caucus to vote against the measure.

“It is not something we could ever support. House Democrats will not be complicit in the Republican effort to hurt the American people,” Minority Leader Hakeem Jeffries told reporters on Monday.

The 99-page bill would decrease spending overall from last year’s funding levels but increase spending for the military by about $6 billion.

While there is an additional $6 billion for veterans’ healthcare, non-defense spending is about $13 billion lower than fiscal year 2024 levels.

The legislation leaves out emergency funding for disasters but provides a boost in funding for Immigration and Customs Enforcement deportation operations.

It also increases funding for W.I.C. by about $500 million, a program that provides free groceries to low-income women and children.

ABC News’ Hannah Demissie contributed to this report