SAN FRANCISCO, Cali - The San Francisco 49ers have worked themselves into the N.F.C playoff hunt by grabbing a 20 to 0 lead in a 20 to 14 win over Seattle. Frank Gore ran for 212 yards on 24 carries, including a 51-yard scamper that set up Joe Nedney's 39-yard field goal in the first quarter. Alex Smith threw for a touchdown and ran for another in the Niners' third straight win, which leaves San Francisco just a game behind the first-place Seahawks in the N.F.C West. He tossed a nine-yard T-D pass to Arnaz Battle, then ran for a one-yard run that put the 49ers ahead 17 to 0 in the second quarter. Smith was 19 of 25 for 163 yards and no interceptions for the 5-5 Niners. Seneca Wallace passed for 252 yards, two touchdowns and three interceptions for the 6-4 Seahawks. Seattle running back Shaun Alexander had 37 rushing yards on 17 carries in his first action since missing two months with a broken foot.