Dozens of committed activists and other opponents of the $1.2 billion expansion of Interstate 70 through northeast Denver lost a big challenge against the project last week, but don’t count them out — not yet. One attorney for an environmental law firm speculated that federal officials’ findings in favor of the Colorado Department of Transportation on a civil rights complaint — one lodged on behalf of the heavily Latino neighborhoods of Elyria-Swansea and Globeville — would only embolden critics fighting the highway in other ways. And there still are several avenues open: Pending and expected lawsuits are taking direct aim at the project and, if successful, could delay or even scuttle it.