WASHINGTON (TNND) — The House Republicans' recently passed spending bill, dubbed the "big beautiful bill," faces significant hurdles in the Senate as Republican senators voice concerns over its potential to increase the national debt. The bill, which includes a $4 trillion debt ceiling raise, has been criticized by several senators for its financial implications.

"I'm sorry, the House Bill would probably add I've calculated $4 trillion. You're saying you have these independent analysts saying it's 3.3 to $4 trillion. I agree with that. We have to reduce the deficit and so we need, we need to focus on spending, spending, spending," Sen. Ron Johnson, R-Wis., told CNN.

The debt ceiling raise, which increases Congress's ability to borrow money to meet financial obligations, is a non-starter for Kentucky Republican Senator Rand Paul.

I support spending cuts, I think the cuts currently in the bill are wimpy and anemic, but I still would support the bill even with wimpy and anemic cuts if they weren’t going to explode the debt. The problem is the math doesn’t add up," Sen. Paul told Fox News.

The House Republicans narrowly passed the bill after intense internal debates over issues such as Medicaid and tax credits.

Medicaid was a particularly thorny issue, with some members of the party worried about making cuts to the program, and others wanting work requirements to kick in sooner. However, if the Senate proposes a version with more cuts and changes to how Medicaid is impacted, it is uncertain whether the House will have the votes to pass it again.

"I have a very delicate balance here, a very delicate equilibrium that we've reached over a long period of time and it's best not to meddle with it too much," House Speaker Mike Johnson, R-La., told CNN over the weekend while emphasizing the fragile nature of a very thin House Republican majority.

President Trump, meanwhile, expects the Senate to make some changes, but remains optimistic about the bill's prospects.

I think the Senate is going to get there. I hope they're going to get there. I think they're going to have changes. Some will be minor and some will be fairly significant," he told reporters over the weekend.

With enough Republican Senators expressing hesitation, another budget battle looms as the summer approaches.

"You don’t always need the whole loaf of bread at once, you can take it slice by slice. You get a lot of great slices, let's move it forward, and make it so we don’t even have to send it back to the House," Rep. Brian Mast, R-Fla., said Tuesday.

Republicans aim to have a finalized bill on the President's desk by July 4.