I agree with John here,
I really don't think there is a specific party which fits Orthodoxy at all. All parties seem to have their pro's and cons faithwise, the already mentioned infamous immigration debate being just one example.
Major issues to look at in m vew would be equalities and how the parties intend to view these as an important part of the faith is not to pass judgement on others. Also there ae issues such as public spending and party policies towards war and military spending.
It is a messy business, especially this election which seems to have attracted more attention than usual and become quite the spin spectacular.
"The true Christian is a warrior making his way through the regiments of the invisible enemy to his heavenly homeland." - St Herman of Alaska.