Even before pre-entries are officially released later this week, we already have a pretty good idea who the betting favorites will be in most of the Breeders' Cup races barring any unforeseen developments between now and the first weekend in November at Churchill Downs.

Here are brief thoughts on several, ranked in order of seeming vulnerability from most to least.

Sistercharlie (Filly & Mare Turf) -- She's tended to cut things close since her importation, winning races like the Diana (G1) and Beverly D (G1) narrowly and losing others like the Belmont Oaks (G1) and New York (G2) in photos. Bruised a foot following the Beverly D score and thus will enter off a layoff approaching three months. Past two editions of the race at Churchill produced wild results, including unexpected losses by defending titlest Midday (2010) and the Brown-trained favorite Stacelita (2011). Quality European invaders figure to make this a difficult test.

Accelerate (Classic) -- Has done hardly anything wrong this year, yet still seems like the one many will prefer to play against for any number of reasons. Flunked on this stage in the Dirt Mile (G1) at his home base of Del Mar last year, and his only race outside California was a losing effort (albeit narrowly) in the Oaklawn H. (G2) to City of Light, who never developed into a distance specialist. Trainer John Sadler has had limited success in major stakes outside California, though Stellar Wind almost won the 2015 Breeders' Cup Distaff (G1) at Keeneland.

Imperial Hint (TwinSpires Sprint) -- Last year's runner-up won the Alfred G. Vanderbilt (G1) and Vosburgh (G1) with extreme facility in his last two. Both prior runs over the Churchill surface were beyond his preferred six furlongs, but they still suggest he could be vulnerable to a horse-for-the-course type. The race is shaping up to be another barn-burner, especially with defending champion Roy H seemingly back to his best form after the Santa Anita Sprint Championship (G1).

Monomoy Girl (Distaff) -- Sophomores don't have a great track record of late, winning just three of the past 13 renewals of this race. That said, she's on her home track and her only hiccup this term was the result of decision in the stewards room last time in the Cotillion (G1). There's not a lot of depth to the field. Division rival Midnight Bisou has finished behind her in all three meetings, while the older Abel Tasman has blown hot and cold this year. Could be tough to overtake if no one else steps up.

Catalina Cruiser (Dirt Mile) -- Some of the concerns folks have about Accelerate in the Classic (e.g. Sadler's record outside the Golden State) could apply to him as well, but made not far-fetched hints that maybe he was the best older horse in the stable with two dominating scores at Del Mar in the San Diego H. (G2) and Pat O'Brien (G2). Undefeated colt faces stronger foes in unfamiliar surroundings this time, but on sheer talent few look as good going into the weekend.

Bellafina (Juvenile Fillies) -- She's proven much the best of her Southern California contemporaries so far. As we noted recently, this edition is shaping up to be one of the most competitive in years, and on paper she doesn't quite stand out like, say, Songbird did. Will still prove very difficult to outrun with her best try.

Marley's Freedom (Filly & Mare Sprint) -- Three-for-three since joining the Bob Baffert stable, including consecutive wins in the Desert Stormer (G3), Great Lady M (G2), and Ballerina (G1). Stalk-and-pounce style fits the profile of this race, though longer-priced entrants have done far better than the favorites. It's not a particularly quick group of foes she'll face, and only an inability to handle Churchill or some other type of unexpected regression would appear to be her primary obstacles.

Game Winner (Juvenile) -- Like Bellafina, he virtually ran out of competition in Southern California with back-to-back wins in the Del Mar Futurity (G1) and American Pharoah (G1). The East Coast contingent, led by Complexity and Code of Honor, are worthy of respect, but Bob Baffert appears to be bringing a very talented colt with an even brighter future.

Enable (Turf) -- The two-time Prix de l'Arc de Triomphe (G1) winner may be the heaviest favorite of the weekend and, on paper, has all the class to break the long jinx that have plagued Arc winners past in this race. That said, the history of the Turf has not been kind to favorites and it's often been won by a European not overly fancied in the wagering. She merits being this far down from a vulnerability standpoint and the fact no specific rival stands out as being her equal, but whether she's "single" material is open to debate given the past trends of this race.

(Benoit Photos)