Republicans Widen Push to Pick Up Senate Seats - President's Sagging Approval Ratings Expand Map of Competitive Races

From The Wall Street Journal:

President Barack Obama's sagging approval ratings and the rocky health-law rollout are expanding the map of competitive Senate races this year, giving Republicans new hope of capturing seats in states that the president carried in 2012.

The GOP already had a strong opportunity to pick up a net six seats to win a Senate majority. Democrats have to defend many more seats than Republicans, including in seven states that Mr. Obama lost in 2012. Now, polls show tighter-than-expected races for Democratic-held seats in Colorado, Iowa and Michigan, while a formidable Republican is challenging the Democratic incumbent in Virginia and another is weighing a bid in New Hampshire. In 2012, Mr. Obama won all five of those states.

With Election Day more than nine months away, the question is whether this marks a low ebb for Mr. Obama and his party, or a lasting trend.

"I'd be more worried if I were a Democrat than if I was a Republican," said Stuart Rothenberg, editor of the nonpartisan Rothenberg Political Report, which tracks congressional elections. "The Republicans' prospects in the existing targets are improving because of the president's approval ratings, and they are continuing to put other races on the board."

A Democratic lead of better than six percentage points in which party voters think should control Congress has collapsed since the glitch-plagued health-law rollout in October, leaving the parties at parity, according to an aggregate of polls by Real Clear Politics.

Adding weight to the Democratic burden: Midterm elections are historically unkind to the parties of sitting presidents, particularly in their second terms. And voter demographics should favor Republicans because the electorate in midterms tends to be older and whiter than in presidential-election years.