Farda Amiga springs 20-1 Oaks upset Farda Amiga sprang a huge upset to win the $500,000 Kentucky Oaks at Churchill Downs today.Ridden by Chris McCarron, 20-1 Farda Amiga defeated favoured Take Charge Lady by 1 1/4 lengths in the 1 1/8-mile race for three-year-old fillies. Habibti was another 1 1/4 lengths back in third.A Churchill Downs crowd of 101,923, the third largest in Oaks day history, watched the race. The California-based winner, trained by Paulo Lobo, had to survive an objection by Habibti`s jockey Victor Espinoza, who claimed interference in the stretch.Godolphin`s Imperial Gesture, ridden by the globetrotting Frankie Dettori, weakened in the stretch and never threatened despite being the 7-2 third betting choice. Dettori returns to England late tonight to ride Godolphin`s Naheef in the 2,000 Guineas at Newmarket tomorrow.'Believe it or not I was confident going into this one,' said McCarron after winning his third Kentucky Oaks. 'I knew my filly would just keep coming.' Farda Amiga paid $42 to win, $11.20 to place and $5.40 to show for a $2 stake. Take Charge Lady, trained by Ken McPeek, whose colt Harlan`s Holiday attempts to take the Kentucky Derby, was sent off at 8/5 odds, paid $3.80 and $3.00, and Habibti paid $3.80 to show.In an earlier race, the D. Wayne Lukas-trained Spain became the richest filly or mare in North American history after winning the Louisville Breeders` Cup Handicap.Spain`s winnings of $207,204 boosted her career earnings to $3,304,244, eclipsing the mark of $3.28 million set by Senena`s Song. Ridden by Jerry Bailey, 3-1 choice Spain defeated Mystic Lady by 1 1/4 lengths in the field of six.