It's obviously OK for a newspaper to present their opinion on the editorial pages, but it's another to accuse one party of being the cause of their angst and ignoring the misdeeds of the opposing party.

Allegations of Electoral Crimes

This editorial goes into alleged misdeeds by a voter registration group paid for (in part?, entirely?) by the Republican National Committee. For anyone who's followed the story on the internet, this has become "proof" that Republicans are ready to steal the election "again".

However, there are plenty of cases of Democrats/leftists trying to affect the election illegaly as well.

ACORN Voter Registration Fraud Allegations Are Just the Tip of the Iceberg

Also see here for links to about 30 examples of voter fraud and violence directed towards Republican efforts by various Democratic/leftist groups.

Cataloging voter fraud and political violence and vandalism

It's still possible that Republicans as a whole are perpetrating more voter fraud than Democrats, but that's not the point.

The fact that the Times singles out one allegedly rogue operation of a Republican is unfair.