PORTLAND, Ore. (AP) _ Alejandro Cruz of Mexico surged ahead of American Steve Spence in the final 150 yards to win the 12th annual 15-kilometer Cascade Run Off on Sunday.

Lisa Weidenbach of Issaquah, Wash., knocked 30 seconds of the U.S. record set by Grete Waitz in winning the women's division. Race winners each received $7,000.

It was a three-man contest at the 10-kilometer mark between Cruz, Spence and Rolando Vera of Ecuador. But Vera fell behind in the final yards to finish third.

The 21-year-old Cruz, competing in his first short-distance race, finished at 42:38, nearly eight seconds better than last year's winner, John Treacy of Ireland. Spence, of Boulder, Colo., was clocked at 42:49 and Vera at 42:44.

Weidenbach, 27, became the first American woman to win the Cascade Run-Off since 1980. She took the lead three miles into the race, finishing in 48:28, ahead of Portugal's 30-year-old Aurora Cunha at 48:44.

Anne Audain, the 33-year-old New Zealander who won last year's race in 49:00.6, finished third this year at 50:11.

In the men's race, Cruz and Vera exchanged leads until the six-mile mark, when Spence entered the picture in an effort to become the first American to win the race since 1981.

''The pace was very good and very fast,'' said Cruz, despite a heavy rain that begin falling when the leaders reached the higher elevations. ''I just waited until the last couple of kilometers to make my move.''

Spence said, ''(I made my) move too soon and I got impatient,'' while Vera, 24, stayed nip and tuck with Cruz.

Weidenbach said, ''I though I was really fresh at (two miles) and felt good about the race. At the seven-mile mark I began calculating that I could win it.''