Among the ads for toothpaste and dish detergent, the loyal viewers of daytime television are seeing a new pitch: Support President Obama.

“Judge Judy,” in fact, has become one of the favorite venues for the Obama campaign and its allies to reach sympathetic voters. When the courtroom reality show featuring a sharp-tongued former judge airs in swing states, it often comes with ads telling viewers that Republican candidate Mitt Romney uses tax havens and has shipped jobs overseas as a businessman.

The show is considered an ideal vehicle for commercials pushing the president’s reelection because such courtroom programs are watched by a large number of African Americans — twice the average share for television in general.

Those shows also disproportionately draw Hispanics, another voting bloc critical for an Obama victory.

With the president and Romney virtually tied in the polls, targeted TV ads have become a central strategy to shore up support for Obama among voters who turned out in force in 2008.

“They’re trying to get people who they can count on,” said Tad Devine, a top media strategist for Sen. John F. Kerry’s 2004 presidential campaign. “There’s not a big audience to persuade out there, so the respective sides are going to their corners.”

That kind of political spending is part of a shift away from advertising during local news broadcasts, long considered a natural spot for campaign ads because they draw the most politically active audience. For more than a decade, both Democrats and Republicans have been gradually moving toward niche audiences who tune into certain network shows or cable channels.

“It used to be that there was a standard political schedule, and now everybody’s got their own strategy,” said Stephen Hayes, the general manager of WTVR, the CBS affiliate in Richmond. “It’s a lot more refined.”

But Democrats are pushing out of the “news box” significantly faster. The Obama campaign and supporting interest groups have aired just one third of their ads during local news this year, compared with half for Republicans, according to Kantar Media/CMAG, which has tracked the more than $200 million worth of broadcast-television advertising in the 2012 presidential race.

Daytime television, however, brings the Obama camp another critical set of voters: women. Three-quarters of the audience for daytime talk shows, for example, is female, according to Scarborough Research. Obama ads are running with programs such as “Dr. Oz,” named for the surgeon host who sometimes trots out human body parts to show the effects of disease.

The same quest for demographic niches explains why the young viewers drawn to reruns of “The Big Bang Theory,” a sitcom about two geeky physicists, will see spots on Obama’s education policy or ones critical of Romney’s stance on insurance coverage of contraceptives.

Daytime ads also have the added benefit of being less expensive, which is especially appealing to Democrats, who are likely to be outspent this year.

Democrats have had a harder time than Republicans in raising the large political contributions allowed under relaxed campaign finance rules. In recent months, conservative groups have outspent the main super PAC behind Obama, Priorities USA Action, 7 to 1 on the airwaves. At the end of June, Priorities had less than $3 million in the bank, compared with more than $53 million for the two biggest conservative PACs backing Romney.

As a result, Priorities USA Action has taken a thrifty approach to television, running fewer than one in four ads during local news and just 1 percent of ads during prime time.

The super PAC is also avoiding some of the more expensive media markets, including Philadelphia, Washington and Miami. In Florida, for example, it is buying time only in Tampa and Orlando, home to vast numbers of swing voters along the Interstate 4 corridor.

“We put a very high premium on the efficiency of the dollars that we spend, because we know we’re going to be outspent,” said Bill Burton, the co-founder of Priorities USA Action. “We micro-target based on demographic and geographic needs.”

Obama’s campaign is spending more than the super PAC, advertising in nine of Florida’s 10 markets. Obama officials declined to comment, and Romney’s campaign did not respond to a request for comment.

Priorities has focused much of its money on ads that run in the early morning and daytime and attack Romney for his record at Bain Capital, the private equity firm he founded. It spent millions of dollars in ads on that subject weeks before the Obama campaign joined the fray.

In one of the commercials sponsored by the super PAC, a man wearing work clothes narrates from an empty factory yard as newspaper headlines announce layoffs.

“With Romney and Bain Capital, the objective was to make money,” the worker says as a freight train rumbles past in the background. “He promised us the same things he promised the United States. He’ll give you the same things he gave us — nothing. He’ll take it all.”

The super PAC’s recent spots, featuring emotional testimonials from workers who say they were affected by Bain’s actions, seem to be talking to unemployed people and shift workers. The hope is that they, too, will be reached through daytime television.

Sometimes, campaigns will shell out for prime-time spots costing upward of $2,000 for a single airing. Republicans prefer dramas and police shows, Kantar’s data show, and Democrats tend to go for lighter fare.

Obama’s campaign, for example, has spent $1 million on ads during ABC’s “The Bachelorette” and Fox’s “So You Think You Can Dance?”

Laura Vozzella contributed to this report.