House Speaker John Boehner (R-Ohio) praised Rep. Fred Upton (R-Mich.), the chairman of the House Energy and Commerce Committee who is facing a potentially tough Tea Party primary challenge.

Upton has a relatively centrist voting record, although it has trended more conservative in recent years. He is facing a rematch against former state Rep. Jack Hoogendyk (R), who held him to 57 percent of the primary vote in 2010 despite spending almost no money on the race.

The deep-pocketed, fiscally conservative Club for Growth has already run TV ads slamming Upton's record, and could spend heavily on the race.

"Well, I don't know much about what the Club for Growth is doing, but I can say this: Chairman Upton has done a marvelous job as chairman of the Energy and Commerce Committee, led the effort to repeal ObamaCare, led the effort to expose the Solyndra, and he's got as conservative a voting record as — as you'll find," Boehner said on Thursday in response to a question about the Club for Growth's attacks. "Frankly, I think he's done a marvelous job on behalf of Republicans here in the House."

Boehner's support could be a big boon to Upton, especially if he decides to help him with fundraising.