With a quarter of a million troops amassing outside Iraq and the city of Baghdad preparing for Armageddon, it’s tough to find anything resembling a silver lining in the headlines. But there was some good news yesterday in the environmental sector: Senate Republicans said they had probably come up short in their efforts to secure enough votes to open Alaska’s Arctic National Wildlife Refuge to oil drilling, the highly controversial cornerstone of President Bush’s energy plan. The Senate will vote on the plan late this week or early next, and by all indicators, the pro-drilling faction is about two votes shy of a success. The expected failure is sure to be an embarrassment for Bush, who vowed while campaigning to undo President Clinton’s refusal to drill in the refuge. Environmentalists said they were cautiously optimistic about the lay of the land, but weren’t going to exhale until after the vote.