The Party that Obama Un-Built

Julian Castro is no Barack Obama. And for that, Democrats have themselves to blame.

The focus of this week's Democratic convention was President Obama. Lost in the adulation was the diminished state to which he has brought his broader party. Today's Democrats are a shadow of 2008—struggling for re-election, isolated to a handful of states, lacking reform ideas, bereft of a future political bench. It has been a stunning slide.

The speech by Mr. Castro, the young and charismatic mayor of San Antonio, was the Democrats' attempt to recapture the party optimism that then-Senate candidate Obama sparked at the 2004 convention. John Kerry didn't win, but that year marked the start of an ambitious Democratic plan to revitalize the party.

In 2006, Nancy Pelosi muzzled her liberal inclinations to recruit and elect her "Majority Makers"—a crop of moderate and conservative Democrats who won Republican districts and delivered control of the House for the first time in 14 years.

Democrats in 2006 also claimed the Senate, with savvy victories in states like Montana and Virginia. The party thumped Republicans in gubernatorial races, winning in the South (Arkansas), the Mountain West (Colorado), and in Ohio (for the first time since 1991). A vibrant candidate Obama further boosted Democratic ranks in 2008.

By 2009, President Obama presided over what could fairly be called a big-tent coalition. The Blue Dog caucus had swelled to 51 members, representing plenty of conservative America. Democrats held the majority of governorships. Mr. Obama had won historic victories in Virginia and North Carolina. The prediction of liberal demographers John Judis and Ruy Teixeira's 2004 book, "The Emerging Democratic Majority"—lasting progressive dominance via a coalition of minorities, women, suburbanites and professionals—attracted greater attention among political analysts. ...