As his first term nears an end, President Barack Obama has lagged behind his predecessors in stocking the nation's federal bench with new judges.

But Obama has had a powerful impact on the Bay Area federal courts and the influential San Francisco-based 9th U.S. Circuit Court of Appeals, two courts where the White House has managed to win confirmation of a cluster of new judges who may mold the legal landscape on crucial issues for years to come.

A second Obama term would give him even more chances to put his stamp on this region's federal judiciary, which has dealt with everything from the legal battle over California's gay marriage ban to the epic patent feud between Apple and Samsung. Republican rival Mitt Romney, meanwhile, has pledged to appoint conservative judges.

Obama already has appointed five of the 14 full-time judges on the Bay Area federal courts, which include branches in San Francisco, Oakland and San Jose. Former President George W. Bush named just one, Jeffrey White, in his two terms.

The Obama administration also has put five judges on the 29-member 9th Circuit, which covers California and eight other Western states. The result is a court now dominated more than ever by Democratic appointees -- 19 members of the court were appointed by Obama or former Presidents Bill Clinton and Jimmy Carter, suggesting the 9th Circuit's liberal reputation will hold firm.

"It's hard to change the character of the 9th Circuit," said Rory Little, a Hastings College of the Law professor. "It's like moving a battleship."

Overall, however, Obama has had trouble building his judicial legacy, although he did appoint two U.S. Supreme Court justices, Elena Kagan and Sonia Sotomayor. He is well behind both Bush and Clinton in appointing judges, prompting grumbling from some liberal organizations that he has failed to take advantage of his first term -- nominating dozens fewer judges than his predecessors did.

"If he gets a second term, we'd certainly call on the president to swing a little more for the fences," said Nan Aron, president of the Washington, D.C.-based Alliance for Justice.

Republicans have thrown political roadblocks in Obama's way, including torpedoing his most controversial 9th Circuit nominee, UC Berkeley law professor Goodwin Liu, later named to the California Supreme Court. Last week, Senate Republicans blocked floor votes on 17 district court nominees, including San Francisco lawyer William Orrick III and Alameda County Superior Court Judge Jon Tigar.

Legal experts say Orrick and Tigar are likely to be confirmed if Obama wins, but their nominations will lapse if Romney takes the White House.

The influx of new judges "changes the dynamic of the court quite a bit," said San Jose U.S. District Judge Jeremy Fogel, now head of the federal judiciary's think tank.

Diversity has been the signature feature of Obama's appointments to the district court and 9th Circuit. In this region, he has appointed Lucy Koh, the first Korean-American female federal judge; two Latinos, Edward Davila and Yvonne Gonzalez Rogers; and another Asian-American, Edward Chen.

The 9th Circuit has added the nation's first Vietnamese-American female appeals court judge, Jacqueline Nguyen, a Latina, Mary Murguia of Arizona, and an African-American, Paul Watford, a former Los Angeles litigator.

The Obama appointees are generally described as moderates.

"I think the 9th Circuit and Northern California appointees are a fair reflection of Obama appointees nationally," said Carl Tobias, a University of Richmond law professor.

Ninth Circuit Chief Judge Alex Kozinski, a Reagan appointee, sees no ideological tilt among the appointees. "I'm always pleased when I find colleagues who I can't tell ahead of time how they are going to vote," he said.

For the most part, the new 9th Circuit judges have yet to make much of a mark, with the exception of Murguia, who has penned both liberal and conservative-style decisions. She broke ranks with a liberal bloc this year, writing the dissent in a 6-5 ruling overturning a teen's conviction for killing a Sacramento pastor.

Several new Bay Area judges have also made their mark, notably Koh, who presided over the high-profile Apple-Samsung trial, drawing attention for controlling the two high-priced legal teams with an iron gavel.

Experts, however, say it will be years before Obama's picks can be graded.

"It's wrong to classify judges by who appointed them," said Kozinski, one of the 9th Circuit's most unpredictable judges. "Judge have their own philosophy and own point view, and it develops over time."

Howard Mintz covers legal affairs. Contact him at 408-286-0236. Follow him at Twitter.com/hmintz.