To Pay off the Mortgage or Not

[afchic]

For the smarter financial folks than me, here is a question.

My husband and I have a home appraised at approx $300K, with a $208K mortgage. If I were to increase our mortgage payments by a hefty amount, and the only thing I would have to do is stop paying into my TSP, leaving my IRA and Mutual Funds as they are, I could pay off our mortgage by the time I retire in 4 years.

Is it better to pay off the mortgage (5.25% loan) or is it better to take that extra money and dump it into my TSP, as well as increase the amount going into my mutual fund.

The home is our only debt. No car payments, no credit card payments, and kids college is already accounted for in our GI Bill.