The far-left fringe of the Democratic caucus is flexing its muscle to try to implement last-minute changes in a $3 trillion spending bill.

The small group of liberals, led by Rep. Pramila Jayapal, has unusual leverage: No Republican is supporting the spending measure, which means Democrats cannot afford to lose many in their caucus if they hope to pass the measure with a majority vote.

The House will vote on the measure Friday, and Speaker Nancy Pelosi is urging her caucus to support it.

According to a top Democratic aide, a small group of lawmakers who participated in a caucus-wide conference call persisted with efforts to try to add a provision to the measure that would provide a basic monthly income for many workers.