Deb,
Signing a contract before the Match isn't a bad idea if you'll sign with a program that you're sure you'll like. I was offered a contract before the match but didn't sign 'cause it wasn't my number one choice. Advantages include knowing where you're gonna go before March (there isn't much time between March and July: I had to sell my house, buy another one, my wife had to find a job...etc) and peace of mind in knowing you're not gonna havta scramble for a spot.
Carefully consider why the program is offering you a contract: Either 1)The program is hurting for residents or 2)You're just that good. Doing a rotation at the program is one way to get a feel for the quality of the training and quality of the residents. Be leary of a program offering you a contract if all they know about you is what's in your application. Fine if you've done a rotation there, but if they're willing to give you a contract based on your personal statement, something's wrong with the program.
I wouldn't try to sollicit a contract, let the program director offer you one. If your top choice doesn't offer you one, you'll have to take your chances in the Match. Many programs won't offer contracts outside the match, so don't get discouraged if you don't get such an offer.
Good luck.
