Translation - 由於.., 因此...

Due to the incredible success of our last event. a second attempt will
be held same as last issue.

incredible success- 令人難以置信的成功
last event - 上一次活動
attempt - 嘗試
same as last issue - 正如上一次一樣


I think it is good enough to describe what you want to express.

2008-04-16 16:14:12 補充：
Due to the incredible success of our last event, a second attempt will
be held same as last issue.

2008-04-16 16:20:12 補充：
last event 後面是, 而不是.

由於/ 基於/ 有鑑於 上次活動的反應熱烈/ 理想，現舉行第二次的同類型活動,,
Since the last activity was tremendously successful, we are now holding a similar one the second time.

由於/ 基於/ 有鑑於 上次活動的反應熱烈/ 理想，現舉行第二次的同類型活動,,
According to the great success of the last activity, we therefore have the second and similar event today.
1/ According to = 基於
2/ 盡量不要在同句中用同一個字兩次, 即 activity/event

In view of the favorable/ideal response of the last activity, we now organize the similar activity again.

Please keep in mind that having "so" after "because" is not a good grammar. It is definitely a "Chinese-English" writing format.

You may consider using "due to", "because of", "as a result of".

e.g.

As a result of the great success from the activity, "name of the activity", we are plaesed to welcome you to join our 2nd round of activity, "name of the activity".....

Beacuse the result of the party was excellent last time, so we are going to hold
the same kind of party in the following day.