Sen. Joe Manchin (D-WV), one of the Democrats who has expressed his opposition to the $15 minimum wage, enters the Senate with Sen. Debbie Stabenow (D-MI). | Tom Williams/CQ-Roll Call, Inc/Getty Images

Democrats may soon have to confront divides in their caucus on the minimum wage.

Once the Covid-19 relief bill heads to the Senate, the $15 minimum wage will face two big tests: one procedural, and one political.

On the procedural front, Democrats need to convince the Senate parliamentarian — an in-house expert who advises on the rules of the upper chamber — that the $15 minimum wage has a significant enough effect on the budget that it can be part of the reconciliation process. Because of a practice known as the Byrd Rule, any policy that’s not seen as sufficiently budget-related can be flagged for removal by