Once upon a time, long before the GOP plummeted to its current status as the Southern and Rural Older White Guy Party, it actually was home to a healthy subspecies known as the Republican moderate.

These moderates roamed the land, cutting deals with Democrats, winning statewide elections, and broadening the GOP's appeal. Pennsylvania alone was fertile turf for people like William Scranton, Richard Schweiker, John Heinz, Hugh Scott, and Arlen Specter. But now, of course, that era is over. Specter has quit the party one step ahead of his own extinction - yet another sign that the Republicans, in their self-defeating quest for ideological purity, have ceased to be a national party.

Naturally, the conservative true-believers are thrilled that Specter is gone ("good riddance"); they've somehow convinced themselves that the loss of yet another Republican Senate seat constitutes a great victory. It's delusional. The more the party shrinks, the happier they seem. I marvel at their ability to resolutely march through the smoking wreckage, all the while insisting that it smells like perfume.

Let us briefly sift the ashes. The party right now has no coherent message, aside from "Do Not Offend Rush Limbaugh." Its messengers are basically conservatives who speak to the choir. It has virtually zilch appeal beyond its base, as evidenced by the '08 election and every subsequent poll; the party is alienating suburbanites, independents, Latinos (the fastest-growing cohort in the electorate), and people under age 30 (the voters who will dominate for the next half century).

A respected nonpartisan group, the Committee for the Study of the American Electorate, summed it up perfectly in a winter report: "The GOP is out of contention in New England and the West. It is getting out of contention in the Mid-Atlantic states and the industrial Midwest. Its bases of former support in the farm Midwest, mountain states, and the South are eroding.

"The only places where the GOP enjoys a durable advantage are Idaho, Utah, Kansas, Nebraska, Alabama, Louisiana, Mississippi, South Carolina, Oklahoma, and Texas. And with the growth of the Latino population, Texas will likely be at least a toss-up state within the next decade." (Actually, pollsters report that 48 percent of Texas Republicans are so angry with President Obama that they want their state to secede from the union. Isn't that unpatriotic? Whatever happened to "My country, right or wrong"?)

Anyway, the GOP's "durable advantage" has been reduced to 10 red states. Two new national polls report that only 20 percent of Americans identify themselves as Republicans, the lowest figure in decades. The holdouts - nationally, and, as Specter discovered, in Pennsylvania - tend to be those who will tolerate no detours from conservative orthodoxy, nor tolerate kind words for Obama.

Specter has left behind a narrowcasted party that would rather marinate in its anger and paranoia than win elections in states outside the heartland and the Old Confederacy. How else to explain the burgeoning popularity of Glenn Beck, the Fox News host, who has been warning of a fascist plot hatched by Democrats? (I'm not kidding. Beck says there's a fascist symbol on the back of the dime in your pocket - a bundle of rods with an axe - and points out that a Democratic president, Woodrow Wilson, approved that artwork in 1916.)

Fortunately, there are still some reality-based Republicans. Kristen Soltis, the research director at a top GOP polling firm, warned the other day that her party "is facing changing demographic forces that present a challenge to its long-term growth." Translation: Unless the party wakes up and diversifies, it is toast.

For starters, Soltis said that if the GOP were to have any chance of connecting with younger voters, it "must shed its image as the party of 'old white guys.' " Indeed, the party's current deficit among the young is dire. In the '08 presidential election, the Republicans lost the under-30 voters by an unprecedented 34 percentage points. And that cannot be simply attributed to Obama's personal appeal; House Democratic candidates won the under-30 voters by 29 points.

Why were the young so decisive for the Democrats? Because they grew up during the incompetent tenure of George W. Bush; because they couldn't warm to a party that appears intolerant and exclusionary. The schism on gay marriage says it all. The young see the concept as no big deal; the party - hostage, more than ever, to its conservative base - equates it with the downfall of civilization. Unless the party modernizes on that issue, its long-term prospects are bleak - which is why John McCain's '08 campaign manager is now urging his party to endorse gay marriage.

To woo the young, the GOP could also use some new voices; a recent Pew poll even reports that 75 percent of Republicans have no idea who the leader of their party is. Lately, the two most prominent spokesmen have been Newt Gingrich and Dick Cheney, which should tell you plenty. Gingrich peaked in 1998, when he was compelled to quit as House speaker. And one can only imagine how young voters view Cheney. Not only does he epitomize the rot of the Bush era, he also looks like a haunted-house character in an old Charles Addams cartoon.

History does teach us that party fortunes fluctuate over time, so I assume the GOP will somehow find its way back. But for now, it reminds me of the college marching band that went astray during the climactic movie scene in Animal House; strutting blindly down a dead-end alley, the musicians ran into a brick wall, and even as they crumpled against one another, they kept on playing the same old music.

Specter found a way out of that alley. Who can blame him?