At least a handful of GOP senators are vulnerable this election cycle, but none more than Mark S. Kirk of Illinois.  

While Sens. Ron Johnson of Wisconsin, Patrick J. Toomey of Pennsylvania, Rob Portman of Ohio, and Kelly Ayotte of New Hampshire are headed for competitive re-election fights, Kirk looks to be facing the most difficult race of all.  

Kirk has won difficult races in the past, but the Democratic presidential nominee next year is likely to win the Land of Lincoln by at least a dozen points (if not far more), and the senator will need to outperform the top of the ticket by a large margin.  

Kirk is still recovering from a stroke he suffered in 2012, making campaigning and fundraising even more complicated than usual. But the reality is the senator — even functioning at full capacity — would likely struggle to hold this seat in a presidential cycle. The last time Republicans won an Illinois Senate race in a presidential year was Charles Percy’s re-election in 1972.  

Rep. Tammy Duckworth, the front-runner for the Democratic nomination, may not turn out to be as good of a candidate as many Democrats expect. But she can probably afford a couple of mistakes as a Democrat running in a Democratic state in a presidential year, while it’s possible for Kirk to run a flawless race and still lose.  

You can read our new, full analysis of the race in Friday’s issue of The Rothenberg & Gonzales Political Report .  

Even though there is nearly a year-and-a-half before the general election, rating the race as a Pure Tossup understates Kirk’s challenge in the race. So we’re changing the Rothenberg & Gonzales Political Report /Roll Call rating to Tossup/Tilts Democratic. That doesn’t mean Kirk can’t or won’t win this race, but he should be regarded as an underdog.  

Related:

Mark Kirk Starts 2016 as an Underdog


Roll Call Race Ratings Map: Ratings for Every House and Senate Race in 2016


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