5 of the senatorial bets declared that should they win in the May elections, they will not use their pork barrel fund whcih amounts to 200 Million a year for each senator.

The 5 senatoriables who said no to pork barrel fund are

ex-Navy Ltsg. Antonio Trillanes IV
Re electionist senator Panfilo Lacson
Martin Bautista
Zosimo Jesus Paredes II
and Adrian Sison

The following article gives more insight on the issue:

5 senatorial bets won’t use pork if elected