Extracting floats from a string in Python

I have this script which can calculate the total of numbers given in a string

total = 0 
for c in '0123456789': 
   total += int(c) 
print total

How should I modify this script to find the total of if the numbers given in the string form have decimal places? That is, how do I need to modify this line:

for c in '1.32, 5.32, 4.4, 3.78':

to find the total of these given numbers.

Will this work?

total = 0
for c  in '1.32', '5.32', '4.4', '3.78':
    c = float(c)
    total += c
print total

It might also work without c = float(c)

    # c = float(c)
    total += float(c)

Thank You!