When the 112th Congress convenes in January, it will include at least 72 new members — one of the largest freshman classes in the nation’s history — at least 63 of whom will join the Republican majority. This year’s crop of GOP candidates was an impressive group, consisting of tea partiers, political novices, military veterans, and a record number of minority candidates, almost all of whom pledged in their campaigns to extend the Bush tax rates, repeal Obamacare, and rein in federal spending. It is a group that promises not only to challenge the Democratic agenda of the past two...