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
Democratic
Democrats
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.
Republicans
Republicans
Next year, the Democrats 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 @placeholder.
Republicans
Republicans
Take three of those four races and the @placeholder will do what they couldn't do in 2010 and 2012: Win back the majority.
Democratic
Democrats
Only three @placeholder incumbents have lost re-election in a decade."
Republicans
Republicans
"Democrats and @placeholder agree on Schweitzer: There was a treasure trove of opposition research.
Democratic
Democrats
"Now we have a list of prospects, and while there's no question that they begin as underdogs in a red state, @placeholder are better off with a candidate that can win rather than a candidate that would self-combust before the 2014 elections."