But a final decision will not be taken until a meeting of the full education committee next week.
Angry opposition councillors walked out in disgust as soon as last night's vote was passed. They fear that existing nursery schools may face drastic cuts in funding if parents use vouchers to shop around.
Yesterday's meeting was intended to work through the issues in order to guide the full education committee, but it quickly lapsed into bitter argument.
'The heads and governors have sent a clear message that they are against phase one of the nursery vouchers scheme. 91% of Milton Keynes heads and governors have said No. However, the Tory councillors are just following the government like sheep.
'They are just going along with it without any thought about what it is going to do for the rest of our education in Buckinghamshire'.
Even Conservatives have reservations about the scheme, according to BBC Three Counties, and last night's vote is no guarantee the county council will go along with the decision.
And last night George Walden, Conservative MP for Buckingham and former education minister, warned that nursery vouchers would widen the gap between private and state schooling.
Speaking in the House of Commons he said what he called 'the government's spatchcock plans' risked entrenching the split at the earliest age. He suggested the government instead should adopt the Liberal Democrats' pledge of promising nursery education for all three as well as four year olds.