1.   The company said it expects between one-half to two-thirds of eligible workers to accept the offer, which expires later this month.

2.   A majority of eligible workers must vote for unionization, so supporters won with a single vote to spare.

3.   About one in four eligible workers participates in a pretax payroll deduction program for health-care or dependent-care expenses or both.

4.   But the unions must represent all eligible federal workers, handling their grievances and negotiating their workplace conditions, even if those employees are not union members.

5.   Ideally, the unions want the federal government to become a union shop, in which all eligible workers are required to become members.

6.   It is illegal for a company to deny disability payments to eligible workers.

7.   It will allow them to offer their eligible workers a cash payment equal to the value of spousal health coverage.

8.   More than half the eligible workers must vote in favor of representation to bring in a union.

9.   Partly because such a tiny fraction of eligible workers has signed up for same-sex benefits, the financial impact has been virtually undetectible.

10.   Some eligible workers are choosing to stay.