California audiences watching the recent Emmycast were more than likely to have seen one of the state’s ubiquitous new stars of local commercial breaks: Meg Whitman, the former eBay chief who is running for governor.

During the past year, Whitman’s become a familiar face on TV and voice on radio in the state, so far spending more than $100 million of her own money to help fund an unprecedented onslaught of ads. And while the spots have introduced her to voters, they’ve also invited a question perhaps more familiar to reality sensations milking their 15 minutes of fame: Is she in danger of overexposure?

The idea that a politico’s ad blurbs can be so plentiful as to begin working against them is embraced by many supporters of her chief rival, Democratic California attorney general Jerry Brown , whether out of earnest belief or mere jealousy. With nothing near her resources, he has yet to air a single spot.

In a blog post last month, Brown campaign manager Steve Glazer cited the Brown campaign’s survey that asked whether those who’ve seen Whitman’s spots have a better or worse opinion of her and Brown. Some 8% said their opinion of Whitman improved, but 27% said it worsened; 31% said it was unchanged. Some 6% said their opinion of Brown improved, 4% said it worsened and 31% said it was unchanged.

The caveat, of course, is that the survey comes from the Brown campaign.

But some of Brown’s supporters, nervous that he’s been all but absent from the airwaves, take heart in the fact that, despite having made a huge outlay, Whitman is even or only slightly ahead of him in the polls.

Barbara O’Connor, most recently the director of the Institute for the Study of Politics and Media at Cal State Sacramento, says overexposure is a “real issue” for Whitman, particularly in the ever-changing media environment.

“She has got to change the mantra,” says O’Connor, adding that it’s especially true in drawing attention in the era of the DVR. “I sit in on focus groups, and what people say is they are now fast-forwarding through the commercials.”

The risk is that the more people see Whitman’s spots, the more they will associate them with her spending huge amounts of her personal fortune to land the governorship, a notion certainly not helped when Jay Leno jokes about it on “The Tonight Show,” O’Connor notes. While Whitman had to start early to introduce herself to voters, and recent spots have been “softer,” it remains to be seen whether she can connect with voters, O’Connor adds.

“She has got to get a message that resonates — ‘What are you going to do to make my life better?’ — and she has got to do it at a very granular level,” O’Connor says.

Ken Sunshine, whose public relations consultancy reps public figures and entertainers, sees parallels between Whitman and Hollywood stars: In the digital age, once you seek attention, you have less and less control over your image.

“Overexposure is a danger, it can backfire, and it is much harder to fight against,” he says.

He sees some comparison to what happened with Michael Bloomberg’s bid last year for a third term as mayor of New York, in which he spent more than $100 million for a push that included an onslaught of TV spots. The race turned out to be unexpectedly close — and his deluge of ads may have backfired, Sunshine says.

But Jack Pitney, professor of American politics at Claremont McKenna College, sees another analogous New York figure: Nelson Rockefeller. He was able to use his personal fortune in his New York gubernatorial bids, yet didn’t stoke resentment.

“You knew one important thing about Rocky: He was never on the take,” says Pitney.

While Whitman may see “rapidly diminishing returns to the advertising at a certain point, where she won’t see as much return from the last million as she does from the first,” he says, “the idea that she’ll be overexposed is just spin.

“What she is going to be able to do with all of her resources is to microtarget and to send slightly different messages to different segments of the electorate.”

According to the Campaign Media Analysis Group (CMAG), Whitman has, since June, run 32,000 TV ads across the state at a cost of $21 million. Brown has run no spots, but he’s been aided by independent groups that have spent $9 million on some 4,000 ads. He’s expected to start running spots soon after Labor Day.

Evan Tracey, president of CMAG, says Whitman’s coffers will prove especially useful in the last 30 days of the campaign, when “elections are won or lost,” and as the race becomes about attracting the last 8% or 9% of undecided voters.

Her campaign last week started running spots in the Bay Area slamming Brown’s tenure as mayor of Oakland. They don’t expect to win the heavily liberal region of the state, but the luxury of being able to spend on that kind of effort means she may chip away at Brown’s lead there.

“There seems to be a lot of variety in what she is running, and they are doing a good job in mixing it up,” Tracey says. “There are so many options competing for people’s time, and the political response has been to just turn up the volume. It’s just hard to see a scenario where she is overexposed.”

In 2008, Barack Obama had to introduce himself to the public and, like Whitman’s, his campaign saturated media markets; ad spots were even embedded in videogames. The blitz proved especially fruitful in the final month before the election, when Obama’s campaign ran just as many or more negative spots than John McCain’s, but it was McCain’s campaign that got slammed for being too harsh. That’s because Obama also was able to also run a concurrent positive campaign, evoking the message of hope and change, Tracey notes.

The same scenario may hold true for Whitman.

“When you have a lot of money, you don’t have to rely on a couple of spots to break through,” he says.

In a recent conference call with reporters, Whitman campaign strategist Mike Murphy said they were pleased with where they were in the race, with several recent polls showing an uptick in her direction.

As much as he is going to be outspent, Brown does have more than $23 million on hand, according to the most recent campaign reports. That’s no small sum, and it’s enough to make himself a familiar presence on the air as well. The wild card is what the impact of such late-innings ads would be, as the environment will be far more cluttered with election spots than it has been up to now, perhaps unlike anything the state has seen.

As O’Connor quips, “Post Labor Day, this will be an airwave war, where people will be about (ready) to throw their television sets out the window.”