Manchin isn't the only problem: This obscure Senate official has the power to derail Biden's agenda

Sen. Joe Manchin has faced pressure from Democrats over his opposition to President Joe Biden's Build Back Better bill, which would invest $1.75 trillion in social spending and climate programs. But Politico on Friday noted that the conservative West Virginia Democrat is not the only potential roadblock to passing the legislation.

The publication explained that the Senate parliamentarian, Elizabeth MacDonough, still has the power to derail the bill.

"Manchin tends to get all of the credit — or take all of the blame, depending on who's speaking — for threatening popular provisions of his party's bill, like an extension of the expanded child tax credit. But the parliamentarian’s office is arguably a bigger hurdle for several of the social spending measure's biggest centerpieces," Politico reported.

The parliamentarian is tasked with ruling on procedural issues in the Senate. "These days, MacDonough's most striking rulings do concern reconciliation bills. In a polarized Senate, where the majority party cannot muster 60 votes to end a filibuster, one of the only ways to get legislation passed is to attach – or 'ride' – controversial measures or provisions through the Senate on a reconciliation bill," explained University of Baltimore law professor Charles Tiefer.

READ MORE: Joe Manchin and the GOP refused Build Back Better — now 9/11 health care program is in jeopardy

Earlier this month, the Senate parliamentarian ruled against Democrats' push to include immigration reform provisions in the Build Back Better bill.

"Democratic leaders believed they had thoroughly pre-vetted the legislation to work under the budget reconciliation process that they're using to pass it along party lines, but the immigration setback still disappointed some in the party," Politico noted.

Several other provisions could be peril, according to Politico, including "tax credits for union-built electric vehicles, caps on out-of-pocket costs for Americans who need insulin and student aid to some undocumented immigrants who came to the United States as children."

The bill aims to funnel funds toward lowering the cost of child care and prescription drugs, supporting the purchasing power of households and investing in the transition to clean energy.

Manchin's opposition to the legislation is a major problem for Biden, who has spent significant political capital in seeking to secure the passage of what is seen as a signature bill of his presidency.

Republicans in the divided Senate solidly oppose the legislation, meaning passage depends on every Democrat in the chamber supporting it.

With additional reporting via AFP