There was a time, more than a century and a half ago, when the Whigs and the Democrats were the nation’s two major political parties.

Whigs elected presidents, members of Congress and state and local officials. They were the party of business, the professional classes and economic centralization.

And then they were gone.

It didn’t happen overnight, but regional differences tore the Whigs apart — and the chief of those differences was, of course, slavery. A series of losses at the national level left former party members — like an Illinois lawyer named Abraham Lincoln — looking for another political home. He and many others found one in the newly formed Republican Party.

True, current developments may evoke the past, but they almost never copy it exactly.

Still, one of our parties faces an identity crisis that could lead to a political transformation almost as significant as the one that brought Lincoln to the presidency and the Republicans to national power.

Some may think I mean the Democrats, who, if the polls can be trusted, are facing something between a drubbing and a disaster on Nov. 2.

But that party, even if it loses one or both houses of Congress and the majority of governors’ offices, won’t fall apart.

Instead, it is the Republicans who are facing a transformative election. And while the party probably won’t collapse and be replaced by a new organization (though if it happened to the Whigs, it could happen again), there is a near-certainty that the GOP will soon be facing a major internal struggle.

That conflict might end up not only in a leadership shake-up but in an ideological transformation that would have significant long-range impacts on the direction of U.S. public policy.

this point, the reason should be obvious, and can be set down with just two words: “tea” and “party.”

The defeat Tuesday of Rep. Mike Castle in Delaware, on top of a series of incumbent primary losses to tea party-backed candidates in other states, has establishment Republicans publicly worried and privately foaming at the mouth.

(The pro-abortion, anti-gun and big-spending Castle was described this week as a “moderate” on both The Atlantic’s website and in the pages of The Washington Post, and as a “centrist” in The Wall Street Journal. What would politicians have to support for those journals to call them “liberals”?)

What apparently got Castle canned in favor of a relatively unknown political neophyte, Christine O’Donnell, was his penchant for voting for bigger and bigger spending bills. As one analyst put it, Republican voters (and, again according to the polls, a lot of independents) have finally gotten fully fed up with voting for politicians who say they are tight-fisted fiscal conservatives on the campaign trail, but who go to Washington to toss taxpayer money around like drunken sailors (except that libels drunken sailors).

That has a lot of implications for the GOP, especially when some of its most promising younger leaders are publishing books calling themselves “Young Guns” and pledging to shoot holes in the deficit and bring down the trillions in unfunded obligations that are the tea party’s chief targets, too.

For public consumption, Democrats and their allies in the national media (sorry to be redundant) are crowing that they couldn’t be happier about all this. To hear them tell it, the swelling support for the tea party’s theme of fiscal responsibility is an iceberg waiting to send the SS Republican Party to the bottom of the sea.

That is, the tea party’s stand is so popular it will inevitably lead to resounding defeat.

OK, Democrats are really saying that tea party support has led to the nomination of candidates who are so extreme that they will lose races that other candidates (presumably ones more to the Democrats’ liking) would have won.

That may be true in Delaware (or it may not — O’Donnell got $500,000 in contributions in the 12 hours following her primary win. And it didn’t hurt her that Senate Majority Leader Harry Reid, behind in the latest polls in his own race in Nevada, twice described her opponent, Chris Coons, as “my pet”).

Republicans, backed by the tea party movement or not, are tied or leading in surprising places, from Florida to Illinois to California to Reid’s Nevada — where his son, running for governor, doesn’t even use his last name in his campaign ads.

Forget Congress for a moment. If the GOP gets control of a majority of big-state statehouses, it will control the scheduled redrawing of congressional districts in the coming year, a near-term kick in the teeth for Democrats.

What do liberals really think? A blog item by The Washington Post’s Ruth Marcus this week let the captive feline out of the recyclable cloth container.

First, she said, the loss of “moderates” like Castle gives fewer allies to other party members who are also out of the GOP’s mainstream: “It’s awfully hard for a caucus of two to break with the party.” Who would those two be, I wonder?

But there’s more: “Republican members of Congress look at races such as those in Utah, Alaska and now Delaware and think: There but for the grace of the tea party go I. They will be that much more watchful of protecting their right flank against a primary challenge.”

Marcus is decrying the potential loss of “bipartisanship” — which, when a liberal uses it, means “Vote with me” and not the other way around.

Sorry if that prospect doesn’t leave me in tears. Transformation seems to be coming, whether big-spending liberals (in either party) like it or not.

Me? I’m off for a steaming-hot cup of Earl Grey. It’s a treat while I wait to see if the Republican Party flips its Whigs.

M.D. Harmon is an editorial writer. He can be contacted at 791-6482 or at:

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