Chris Cillizza at the Washington Post writes:
The decision by Sen. John Walsh (D-Mont.) not to seek election in November in the wake of a plagiarism scandal is the latest piece of good news for Republicans as they strive to take control of the Senate in less than three months.
Walsh’s departure from the race came in the same week that two Republican senators — Pat Roberts in Kansas and Lamar Alexander in Tennessee — defeated tea party challengers in primary fights, ensuring that every GOP senator seeking reelection would be the party’s nominee.
These past seven days typified the fates of the two parties this election cycle. Democrats have been hit by retirements in tough states — Montana, West Virginia, South Dakota and, to a lesser extent, Iowa — and Republicans haven’t nominated the sort of extreme candidates who lack broader appeal in a general election.
Those realities — along with a national playing field in which a handful of incumbent Democrats are defending Republican-leaning seats in places where President Obama is deeply unpopular — have made a GOP takeovera better-than-50/50 proposition.
Nate Silver agrees:
The problem for Democrats is that this year’s Senate races aren’t being fought in neutral territory. Instead, the Class II senators on the ballot this year come from states that gave Obama an average of just 46 percent of the vote in 2012.1
Democrats hold the majority of Class II seats now, but that’s because they were last contested in 2008, one of the best Democratic years of the past half-century. That year, Democrats won the popular vote for the U.S. House by almost 11 percentage points. Imagine if 2008 had been a neutral partisan environment instead. We can approximate this by applying a uniform swingof 11 percentage points toward Republicans in each Senate race. In that case, Democrats would have lost the races in Alaska, Colorado, Louisiana, Minnesota, New Hampshire, North Carolina and Oregon — and Republicans would already hold a 52-48 majority in the Senate.
It therefore shouldn’t be surprising that we continue to see Republicans as slightly more likely than not to win a net of six seats this November and control of the Senate.
Harry Reid may come to regret effectively abolishing the filbuster. If the Democrats go into the minority, they will have sacrificed the tool that could require the majority to work with them.