For several days, the prospects for preventing a railroad strike or lockout rested with a handful of leaders from labor, industry, and government, whose marathon talks led to a tentative agreement Thursday. What happens next depends on more than 100,000 workers represented by a slew of different unions, who'll have to decide whether to ratify their leaders' deal or reject it, setting the stage for a massive work stoppage.

The tentative deal, the text of which hasn't been publicly released, includes record wage increases and new protections, but it doesn't include the paid sick days workers sought, according to union leaders. If approved, the agreement would mark the end of a saga that risked disruptions to the supply chain of the world's largest economy. A strike could cost the U.S. economy as much as $2 billion per day, according to some estimates.