Fine Gael has an incumbency problem.  In fact, the party has two incumbency problems.  And those two problems are now starting to manifest themselves in the opinion polls, which are showing a dangerous downward trajectory.  The first relates to the length of time it has been in government. Sinn Féin has not landed many telling blows on the coalition throughout this campaign but it has succeeded in highlighting the omnipresence of Fine Gael and Fianna Fáil over the last 100 years. Even if the opposition party has not convinced most people that it is offering a genuine path to power,…