Washington CNN  — 

As President Joe Biden pursues a bipartisan Covid-19 relief deal, Senate Democrats are laying the groundwork for passing relief without any Republican votes using a procedural shortcut known as budget reconciliation.

Reconciliation could allow Democrats to fast track key aspects of Biden’s agenda, from Covid-19 relief to infrastructure, but the process comes with a strict set of rules attached.

Here’s what you need to know:

What is budget reconciliation?

The reconciliation process was set up as part of the 1974 Congressional Budget Act to make it faster and easier to pass legislation related to spending, taxes, and debt, because debate on the bills is limited to 20 hours and can be passed on a simple majority vote.

Budget reconciliation allows lawmakers to bypass the 60-vote threshold typically required for breaking filibusters and moving legislation forward.

Democrats currently control exactly 50 seats in the 100-seat chamber, and Vice President Kamala Harris holds the tie-breaking vote in her capacity as Senate president. That’s enough for Democrats to be able to use reconciliation to pass some kinds of legislation.

What can be passed using budget reconciliation?

Bills are only eligible for the budget reconciliation process if they affect federal revenue or spending.

They are subject to what’s known as the Byrd rule, a multi-pronged test designed to keep out provisions considered extraneous, without any real impact on the budget, or that might affect Social Security.

It is named for the late former Sen. Robert Byrd, a Democrat of West Virginia, who decried reconciliation bills for being loaded up with provisions considered far afield from their original purpose. In more colorful Senate jargon, provisions being scrubbed by the parliamentarian are undergoing a “Byrd bath.” When they don’t pass muster with her and are removed from the bill, they are called “Byrd droppings.”

As the committees write their bills, they will try to ensure their proposals will be approved by Senate Parliamentarian Elizabeth MacDonough who must enforce the Byrd rule. Senators can challenge the parliamentarian’s decisions and vote to waive the Byrd Rule, but they would need a 60 vote majority to do so.

When has reconciliation been used before?

Reconciliation has been used many times by both parties to pass controversial legislation over the objections of the minority party, including former President Barack Obama’s Affordable Care Act in 2010 and Trump’s sweeping tax cuts in 2017.

How will budget reconciliation be used for the Covid package?

Democratic leaders Nancy Pelosi and Chuck Schumer introduced a budget resolution Monday, the first in a two-step process that will allow the work of writing the coronavirus relief bill in committees to begin.

The budget vote now will clear the way for Democrats to potentially pass their relief bill by late February or March after the impeachment trial of former President Donald Trump is completed in the Senate.

Embedded in the budget resolution will be reconciliation instructions for several committees to write legislation, which in this case would deal with different aspects of Biden’s Covid relief, including funds for vaccines production and distribution, unemployment insurance, stimulus checks and more.

The formal reconciliation instructions will “direct one or more committees to recommend changes to existing law to achieve specified changes in spending, revenues, deficits, and/or the debt limit. Instructed committees can comply with their targets by making changes to any of the programs under their jurisdiction,” according to the House Budget Committee, which is chaired by Democratic Rep. John Yarmuth of Kentucky.

What timetable are Democrats looking at for reaching a final package?

The party is mindful that they have to move their legislation by mid-March, when enhanced unemployment benefits for people impacted by the pandemic recession are set to expire.

The House would have to pass the budget resolution first and then send its version to the Senate. If the Senate amends it, the House would have to pass it again before the committees could begin work on the reconciliation instructions.

Where do things stand in the Senate?

Senate Majority Leader Chuck Schumer is still working to shore up the support from centrists in his caucus – including Sen. Joe Manchin of West Virginia – to ensure he has the 50 votes needed to pass the budget resolution with a tie-breaking vote from Harris.

He can’t lose one Democrat in his caucus.

In the Senate, debate on the resolution will be limited to 50 hours on the floor. But before a final vote occurs, senators can offer an unlimited number of amendments to the resolution in a process referred to in Senate parlance as a “vote-a-rama.”

This time-consuming and stamina-challenging ritual often stretches past midnight and allows senators, through the amendments they offer, to highlight issues important to them and try to score political points by forcing politically sensitive votes on their opponents.

What are Republicans saying?

Republicans are frustrated that Democrats are threatening to use the aggressive tactic while bipartisan efforts continue, arguing it would set a partisan tone for the rest of Biden’s presidency.