NEW : Bipartisan group of senators announce an agreement . NEW : Plan would cap rates on many types of student loans . New : The plan is expected to be approved by the Senate Finance Committee, which will vote next week. Sen. Tom Harkin , whose support is key , agreed to the deal .
NEW : Bipartisan group of senators announce an agreement . NEW : Plan would cap rates on many types of student loans . NEW : Senate will vote on plan `` as quickly as possible , '' says Reid . Sen. Tom Harkin , whose support is key , agreed to the deal .