Sen. Mark S. Kirk, R-Ill., is adamant he will seek re-election in the Land of Lincoln, giving forceful declarations of his intentions to national and local press.
Privately, Democrats and Republican operatives express concern about Kirk's ability to withstand the strenuous task of a statewide campaign. Kirk suffered a stroke in January 2012 that left him with some mobility challenges.
But Republicans also say Kirk is probably the only Illinois Republican who could keep this seat in 2016. The Republican held a Democratic-leaning House seat in the Chicago suburbs for a decade before ascending to the Senate in 2010.
Kirk will face an uphill route to victory in Illinois. The state voted for President Barack Obama with 25- and 17-point margins in 2008 and 2012, respectively.
The big question is: Which Democrats choose to run against him?
Three members of the state's House delegation — Reps. Tammy Duckworth, Cheri Bustos and Bill Foster — are actively considering bids , according to Illinois Democratic operatives.
Both Duckworth and Bustos have close relationships with Illinois' Senior Sen. Richard J. Durbin, who has declined to publicly pick a favorite so far. Durbin's involvement in the general election will also be notable because of his close working relationship with Kirk.
In the meantime, watch Kirk's voting record over the next year. In the lame-duck session, for example, Kirk was the sole Republican to vote for Obama's surgeon general nominee who was opposed by conservative groups like the NRA. He'll need to make an extra effort to appeal to Democrats who could split their tickets and vote for him in a presidential cycle.
Editor's Note: Over the next two weeks, Roll Call will unveil its Top 10 Races to Watch for 2016. The final edition will run Jan. 2 with the full list. The first race to watch is Pennsylvania Senate .
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