The Club for Growth endorsed six Republican senators up for re-election in 2016 — including three top Democratic targets .
The club, a fiscally conservative group sometimes at odds with GOP leaders, announced Wednesday it is backing Sens. Ron Johnson of Wisconsin, Mike Lee of Utah, Rand Paul of Kentucky, Marco Rubio of Florida, Tim Scott of South Carolina and Patrick J. Toomey of Pennsylvania.
“The pro-growth class of 2010 has done excellent work in the United States Senate," Club for Growth President Chris Chocola said in a statement. "Our members want to make sure they stay there for another six years."
Johnson and Toomey, both swept into Congress in the 2010 GOP wave, start the cycle with targets on their backs. They are running in states President Barack Obama carried by significant margins in both 2008 and 2012.
Rubio, who is reportedly mulling a presidential bid, will also likely face a competitive Democratic challenge. The presidential swing state is one Democrats could spend heavily on in their quest to re-take Senate control.
There were a few notable omissions: Sens. Kelly Ayotte of New Hampshire, Rob Portman of Ohio and Mark S. Kirk of Illinois, all running in competitive states but who rank lower on the club's legislative scorecard .
In 2014, the club spent big in GOP primaries against Republican incumbents, including Idaho Rep. Mike Simpson and Mississippi Sen. Thad Cochran, who both prevailed. That spending rankled national Republicans , who were focused on increasing their majority in the House and taking control of the Senate.
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