Indications are growing that first-line center Nicklas Backstrom may return to the Washington Capitals as soon as tonight, when his team entertains the lowly Montreal Canadiens. Backstrom has missed 40 games since he was elbowed in the head by Rene Bourque, who will be in the Canadiens' lineup tonight. But, by all accounts, Backstrom, a 24-year-old Swede, has fared well physically since he began skating again on March 13. Over the past week, Backstrom's recovery made significant progress. First, he received clearance to take part in full-contact practices; he then passed a neuropsychological test, which is required by the NHL before he can play again.