Appears that there are very, very few.
Its hard to say who among the Republican freshmen will become important House leaders, because there has been too little time to demonstrate leadership potential. It is easier to say who has shown the electoral potential to be a strong future candidate for statewide office, by winning impressively in tough districts in 2010. Sean Duffy in WI 7 won an open seat at age 39 in a D+3 PVI district by 8%, and redistricting made the seat 3% more Republican, so he should win in 2012 and be a potential statewide candidate in a few years. Lou Barletta in PA 11 unseated an incumbent in a D+4 PVI district by 10%, and got a seat 10% more Republican in redistricting; he should be a leader among immigration restrictionists in the House for years to come. Adam Hinzinger in IL 11 unseated an incumbent in a R+1 PVI district by 14% at age 32, and recently defeated 20-year incumbent Don Manzullo in the 2012 Republican primary to ensure himself a second term in a fairly safe Republican district that he should have no trouble holding for the next 10 years. Hinzinger is a definite possibility for statewide office in the future in Illinois, a blue state where only the strongest Republican campaigners have a shot at winning statewide.
At The Washington Post
At The American Prospect