Washington (CNN) -- It's the biggest storyline heading into next year's midterm elections: Will Republicans succeed in taking control of the U.S. Senate? Republicans argue that an announcement over the weekend vastly improves their chances. Democrats vehemently disagree. The news from Montana's former Democratic Gov. Brian Schweitzer. The man known for his signature bolo tie said he would not run for Senate next year, as many Democrats had expected. Schweitzer captured nearly two-thirds of the vote in his 2008 re-election as governor of the red state and was seen by many as the best chance for the party to keep the seat of retiring Sen. Max Baucus blue.
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Former Democratic Montana Gov. Brian Schweitzer decides he won't run for Senate
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Schweitzer was a favorite because of name recognition and electoral success in red state
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Recent reports have tied Schweitzer to nonprofit group with questions about practices
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Democrats are defending far more Senate seats in 2014 than Republicans
Next year, the @placeholder will try to maintain their majority in the Senate, where they currently hold a 54-46 edge (including two Independents who caucus with the party) over the GOP.
"Democrats and @placeholder agree on Schweitzer: There was a treasure trove of opposition research.