I have created a table in my DB to make a poll, and now I have the necessity to count the votes using an IP filter.
This is my table:

ID (auto-increment colum)
DESTINATION (1 = Italy, 2 = Franch, 3 = Usa)
DATE (votation date)
IP (IP of the votants)

Now, I have to count how many votes receive the destination 1 (Italy), destination 2 (Franch) and destination 3 (Usa) COUNTING THE IP ADDRESS ONE TIME PER DATE. That is to say that I want to eliminate all the people (IP) that have voted more than one time in the same day.

This is an example of my data in the table:

(ID, DESTINATION, DATE, IP)
1 - 1 - 29/10/2008 18.29.41 - 87.16.176.3
2 - 2 - 30/10/2008 18.29.41 - 87.16.176.3
3 - 3 - 30/10/2008 18.30.08 - 87.16.176.3
4 - 3 - 30/10/2008 18.30.13 - 87.16.176.3
5 - 3 - 30/10/2008 18.30.19 - 87.16.176.3
6 - 3 - 30/10/2008 18.30.28 - 87.16.176.3

The IP = "87.16.176.2" in the day 30/10/2008 has voted for 5 times, I would like to count ONLY his first vote:

DESTINATION = 1 IN THE DAY 29
(ONLY) DESTINATION = 2 IN THE DAY 30

I have written this SQL query:

SELECT
IP, Data, COUNT(Destination) AS Dest
FROM
Statistiche
GROUP BY IP, Data

but this is the result:

(IP, Data, Dest)
87.16.176.3 - 30/10/2008 18.29.41 - 1
87.16.176.3 - 30/10/2008 18.30.08 - 1
87.16.176.3 - 30/10/2008 18.30.13 - 1
87.16.176.3 - 30/10/2008 18.30.19 - 1
87.16.176.3 - 30/10/2008 18.30.28 - 1
87.16.176.3 - 31/10/2008 10.31.53 - 1
87.16.176.3 - 31/10/2008 10.31.58 - 1
87.16.176.3 - 31/10/2008 10.32.04 - 1
87.16.176.3 - 31/10/2008 10.32.42 - 1

I've tried to use the DISTINCT(Data) command but it doesen't work...

Is it possible to do what I need to do or I have to use some algorithm to do it programmatically and not using an SQL instruction?

Some help?