The Amazing Race's seventh season has loyal aficionados scratching our heads. The early favorites to win — brothers Brian and Greg

and boyfriends Lynn and Alex — all bit the dust. This month the final four battle it out to see who'll take home the $1 million prize by landing first on host Phil Keoghan's finish mat. Which Racers will end up with the bucks and the bragging rights? weighs the percentages of the dynamic duos most likely to succeed (and fail).

Meredith and Gretchen
Vital stats: The underdog married couple has run at the back of the pack for the entire season. At ages 69 and 66, respectively, however, these retirees are the oldest pair ever to make it this far into game. And they haven't had a cakewalk of it. In South Africa, Gretchen suffered a head trauma, causing them to arrive last at the pit stop — where Phil confiscated all of their money and possessions, save their passports. These comeback champs may be senior citizens and a long shot for the final prize, but they've earned our respect by lasting as long as they have.
They could win if... they stay motivated and take advantage of their current second place spot. But if their occasionally defeatist attitude rears its ugly head again, all the luck in the world won't help.
Chances of winning: 25 percent

Ron and Kelly
Vital stats: He's a former POW from the U.S.-Iraqi war; she's a beauty queen. Seems like they should have all their bases covered, but the squabbling daters landed in last place in Istanbul. Thanks to a non-Philimination leg, they're still alive in the game. Unfortunately, they'll start the next leg with no cash and no belongings. (We'll bet Ron's probably still smarting from Kelly's assessment that his patterns in life show he can't commit because he "got out" of being in the military by being a POW.)
They could win if... Kelly keeps her irritating barbs to herself and the couple avoids allying with Rob and Amber, who are unlikely to help them out in the final leg. Even if they should win, it might be bittersweet, since the Race seems to have wreaked havoc on their fragile relationship.
Chances of winning: 60 percent

Uchenna and Joyce
Vital stats: This married couple is currently in first place. They're arguably the team most in need of the $1 million due to the financial burden of their efforts to have a child. But they're also the most deserving, having unconditionally supported each other and remained genuinely enthusiastic about the entire experience, even through tough challenges. Hopefully, Joyce's bravery during the ritual head-shaving fast forward — which propelled them into the lead — has earned them enough good karma to stay at the head of the pack.
They could win if... they can stop Rob and Amber.
Chances of winning: 80 percent (upped to 85 if you add points for our wishful thinking)

Rob and Amber
Vital stats: The engaged couple teamed up once for Amber's win on Survivor: All-Stars (Rob was the runner-up) before they reappeared as the love-to-hate pair on The Amazing Race. It's a good thing that bickering has not marred their success, since the schemers have made very few friends along the way. They didn't slow down when Brian and Greg's truck overturned, refused to give a desperate Meredith and Gretchen any cash, avoided an overeating road block by taking advantage of a loophole... the litany of sins goes on. Many have questioned whether they've played fair. Well, maybe it's not fair that they've changed the rules of the Race forever, but these fierce competitors have forced others to step up their game.
They could win if... They don't get overconfident and make stupid mistakes like underestimating Uchenna and Joyce. Even if they don't take home TAR's top prize, they have already scored big — their fantasy wedding is set to air on CBS during May sweeps.
Chances of winning: 98 percent