Embattled Republican incumbent US Senator Susan Collins of Maine scored a come-from-behind election victory as her challenger conceded Wednesday, virtually closing Democrats' pathway to regaining control of the Senate. "I just received a very gracious call from Sara Gideon conceding the race," said Collins, 67, who had trailed for months in polling against her Democratic rival. Gideon said in a televised address that she spoke with Collins and "congratulated her on winning this election," which chalks up another victory for Republicans from Tuesday's election. Republican are defending their 53-47 majority in the Senate, and Gideon's loss makes it that much more difficult for Democrats to win back the upper chamber of Congress. mlm/sst