WILMINGTON, Del. – One of the great truisms of 20th-century politics, attributed to legendary House Speaker Tip O’Neill, is that all politics is local. If this year tells us anything, though, it’s that O’Neill’s adage may now be as much a part of history as he is.

Just take the example of Christine O’Donnell, the Republican Senate candidate in Delaware. O’Donnell is ubiquitous on conservative cable shows and talk radio, with her candidacy hyped by the likes of Rush Limbaugh and the Tea Party Express, based in California. But you can barely find a trace of O’Donnell or her campaign in Delaware itself, a state that is smaller than some national parks.

Whatever else O’Donnell may symbolize, she stands for the idea that politics in the online age is increasingly borderless and can often be shaped more by national causes than by anything having to do with local constituents.

O’Donnell, a perennial protest candidate and conservative provocateur, became a celebrity among Tea Party types in the weeks leading up to the Sept. 14 primary, in which she beat Rep. Michael N. Castle, the party leadership’s preferred candidate, by about 3,500 votes. The bulk of the contributions her campaign has received have come from outside Delaware, according to the Center for Responsive Politics, and until this week she had no campaign office in the state. She and a few aides were working out of her townhouse.

If O’Donnell is actually running anything like a traditional campaign for the Senate, there isn’t much evidence of it right now. The campaign’s website lists no public events at which voters or reporters can meet her or hear her speak. (And in any event, O’Donnell has declared herself off limits for interviews with national reporters.) Last week, a spokeswoman for Shirley & Bannister, a Virginia-based consulting firm that the O’Donnell campaign recently hired, said she would find out about any scheduled appearances by the candidate, but then she stopped returning e-mails.

At the state Republican headquarters in Wilmington, staff members said Monday that they had no information about whether O’Donnell was out campaigning. A pile of O’Donnell yard signs, leaning against a wall near the door, was the only obvious signal that the party even had a Senate candidate. (The headquarters continues, though, to get calls from out-of-state voters who are furious at the local party for not supporting O’Donnell.)

The large Texan who answered the door at O’Donnell’s townhouse – he said his name was Dave – provided the number for the campaign’s new headquarters in a nearby office park. Reached by phone there, O’Donnell’s press secretary, Chris Merola, said the headquarters wasn’t yet open and that the campaign might be able to receive a visitor there "sometime in the future." As for any coming campaign events, Merola told me, "We’ll have to play that by ear."

Mostly, Merola repeated my questions as if I were speaking in an unintelligible accent.

"Will there be events later this week?" I asked.

"Will there be events later this week?" Merola answered slowly.

And so on.

Meanwhile, O’Donnell’s Democratic opponent, Chris Coons, the New Castle County executive, was happy to tick off the major events he attended last weekend – the annual NAACP dinner, an AIDS Walk, a "mud run" (don’t ask) that attracted thousands of Delawareans. He said he hadn’t crossed paths with O’Donnell at any of them, and in fact, as he thought it over, Coons said he hadn’t seen his opponent since they debated Sept. 16.

Since Delaware is a state without its own media market – Wilmington is effectively part of greater Philadelphia for ad-buying purposes – old-fashioned retail politics has been considered especially crucial here.

"This is a job interview," Coons said. "In Delaware, if you want the job, people expect to meet you."

But O’Donnell is not an old-fashioned kind of candidate – nor is she an anomaly. As money and media coverage cross state borders more easily than ever, driven by fiery commentators and online groups, we are bound to see politicians who are popular vehicles more than they are actual candidates, instruments of resentment whose grass-roots support may emanate mostly from states they have never visited.

A Web appeal can now raise more money overnight than any number of arduous receptions at local hotels. (O’Donnell is said to have pulled in more than $2 million in the past few weeks despite her near-invisibility.) Personalities like Glenn Beck and Sarah Palin may propel more like-minded voters to the polls – at least in a primary – than a local party apparatus can muster.

Anti-establishment vehicles like aren’t new in U.S. politics, of course. What’s different now is that the vehicle doesn’t seem to need an insurgent party behind her, or even an actual campaign, to upend the old order.

Democrats saw the first effects of this in 2006, when Ned Lamont, a Connecticut cable executive with a personal fortune, found himself adopted by bloggers and Hollywood celebrities as a vehicle against Sen. Joseph I. Lieberman and the Iraq war. (Lamont defeated him in the Democratic primary, but Lieberman kept his seat by running as an independent in the general election.) Palin emerged as a similar kind of vehicle after the 2008 election, quitting her job as governor of Alaska and using conservative and social media to build her national following without an office to campaign for.

And then came this year’s Republican primaries, which elevated a succession of little-known vehicle candidates in states like Alaska, Colorado, Kentucky, Nevada and Utah. Like a series of dominoes, each Tea Party-influenced victory seemed to add more urgency and momentum to the next, culminating in O’Donnell’s upset of Castle.

As it turns out, O’Donnell’s campaign has held a few events this week, but they were not meant for voters in general, only for her ardent supporters, who were notified by e-mail. On Tuesday night, about 100 volunteers crowded a Grotto Pizza in Newark, Del., to get yard signs and sign up for canvassing. Many of them seemed to have met before.

The pizza place is about 10 minutes from O’Donnell’s townhouse, but the candidate never appeared.