Sen. Mark S. Kirk’s decision not to campaign this year against his in-state Democratic colleague should come as no surprise.  

While Kirk has said he will support the Republican ticket in November and has committed to actively assisting the party’s gubernatorial nominee Bruce Rauner, the Illinois Republican told the Chicago Sun-Times’ Lynn Sweet that he won’t be stumping for Republican Senate nominee Jim Oberweis.  

Kirk said he wants to protect his working relationship with Democratic Sen. Richard J. Durbin by “not launching into a partisan jihad.” But there are other equally compelling reasons not to hit the campaign trail against Durbin. The Senate majority whip is already overwhelmingly favored to defeat Oberweis, a state senator, dairy magnate and perennial candidate who’s lost several congressional elections already , and no amount of Kirk appearances are likely to change that. Kirk will be up for re-election in two years in this solidly Democratic state, where his ability to work with both parties is a crucial asset to his success. And it’s an added bonus if Durbin feels less inclined to stump against Kirk in 2016.  

As Kirk said in a wide-ranging January interview with CQ Roll Call, he is already preparing for what should be a competitive race in 2016. He won President Barack Obama’s former seat in 2010 with 48 percent of the vote, and he will likely enter the next election cycle as a top Democratic target .