Several Kentucky Derby hopefuls have started to arrive at Churchill Downs.Tuesday's arrival was particularly exciting, as Omaha Beach is considered one of this year's top contenders.Omaha Beach recently won the Arkansas Derby. It vaulted him into second place on the Kentucky Derby leaderboard.Starting from the No. 3 post at the Arkansas track, Omaha Beach was up front by the halfway point on a sloppy track and dueled Bob Baffert-trained Improbable the rest of the way. Improbable arrived in Louisville on Monday.Omaha Beach is ridden by Mike Smith and trained by Richard Mandella.You can watch him race May 4 at Churchill Downs during the 145th Kentucky Derby.