A towering but genteel figure, Hatch was seen as the potential Republican domino — the first GOP senator beyond the four in the bipartisan group that crafted the immigration bill to join the effort. A yes from Hatch, the bill’s supporters hoped, would heighten the odds of support from the GOP as the bill moved to the full Senate.

Getting Hatch’s vote was such an intense pursuit that it rearranged the committee’s workload. While the hourly grind of amending the bill was underway in the hearing room, senators worked behind the scenes to test what would happen if they added some measures and subtracted others to make Hatch happy…

Bridging the divide was the work of one of the top architects of the bill, Sen. Charles E. Schumer (D-N.Y.). Schumer courted Hatch with one phone call after the other, ferrying proposals on a sometimes hourly basis — including over last weekend. Twice, behind closed doors, the senators who wrote the bill met to discuss the Hatch amendments.

“The compromise, I think, is balanced and fair,” Schumer said Tuesday.