Vitter has announced a bid for governor, leaving the future of his Senate seat in flux in 2016. (Bill Clark/CQ Roll Call File Photo)
The 2016 cycle could feature the fewest open Senate seats in at least a decade.
Of the 34 senators facing re-election next year, just one has announced retirement. A CQ Roll Call survey of the entire Senate class showed only one more senator publicly undecided about re-election, plus three additional senators considering bids for other offices. Two more Senate offices did not return requests for comment on re-election plans, though Democrats are near certain one of them — Sen. Ron Wyden, D-Ore., will seek another term.