A Fine Gael minister has endorsed a former Fianna Fail senator in her bid for re-election.

Leo Varadkar says he's backing Averil Power, who is running on the Trinity panel for re-election to the Seanad.

The former Fianna Fáil member left the party after the marriage equality referendum.

But Leo Varadkar says he's been a long-term admirer of Averil Power's work, since their time together in Trinity College:

There are 15 candidates in the running for Trinity's three Seanad seats - none of whom are formally declared as Fine Gael candidates.

All three of the outgoing senators - David Norris, Ivana Bacik and Sean Barrett - are seeking re-election.

While senators do not officially declare a party affiliation when running, senators elected through university panels can sometimes become members of parliamentary parties afterwards.

Ivana Bacik was elected as an independent but serves as Labour's leader in the outgoing Seanad, for example.