Updated

The editors at the biggest newspaper on the West Coast, who were expected to endorse Sen. Barbara Boxer in her primary campaign against token opposition, have decided to remain neutral, saying the California Democrat doesn't display enough intellectual firepower.

The left-leaning Los Angeles Times on Friday declined to offer endorsements in all Democratic and Republican primaries for governor and Senate, saying the races have been undermined by politics and money.

But the newspaper's decision to sit on the sidelines for the Boxer race could prove to be the most damaging of all, given the newspaper's criticism of the three-term senator.

"On the Democratic side, we find that we're no fans of incumbent Barbara Boxer," the newspaper said in an editorial Friday. "She displays less intellectual firepower or leadership than she could."

The newspaper said Boxer's opponent, Robert "Mickey" Kaus, was not a "realistic contender," but it praised him for asking "pertinent questions about Boxer's 'lockstep liberalism' on labor, immigration and other matters."

"But we can't endorse him, because he gives no indication that he would step up to the job and away from his Democratic-gadfly persona," the newspaper said.

Boxer campaign manager Rose Kapolczynski said she was not surprised that the Times didn't make an endorsement since the newspaper has never made an endorsement in a primary involving Boxer before.

In a statement on his website, Kaus, a professional blogger, suggested he was satisfied with the newspaper's decision to endorse no one, but took issue with suggesting being a gadfly is a bad thing.

"I think there is a role for gadflies and for people who turn over ideas and question dogmas. That's what the Senate was supposed to be all about. But people want a leader too, and I would intend to be one. They obviously don't think Boxer is," he wrote.

The Times left the door open for an endorsement in the general election.

"The fast-growing population of California voters who no longer affiliate with a party are seeking a dynamic and creative representative to help direct national policy," the newspaper said. "But the substantive debate about whether Boxer or the Republican nominee is the best person must wait until after the primary. Then, we hope, it will be possible to endorse a candidate."

This is not the first time the Times has remained neutral in a Boxer race. The newspaper didn't make an endorsement in 1992 when Boxer first won election to the Senate, winning a tight three-way race in the primary and defeating conservative commentator Bruce Herschensohn in the general election.

In 1998, the Times endorsed Republican candidate Matt Fong, whom Boxer beat by 10 percentage points. In 2004, the Times endorsed Boxer for the first time in her general election rout of GOP candidate Bill Jones. Boxer didn't face any primary opposition that year.

Boxer is facing her toughest re-election bid this year as she seeks a fourth term. Californians face a double-digit unemployment rate, making many once-untouchable incumbents, like Boxer, vulnerable in November.

Polls have shown Boxer running about even with the three Republicans -- state Assemblyman and Tea Party favorite Chuck DeVore, businesswoman Carly Fiorina and former Rep. Tom Campbell -- who are competing for the GOP nomination in the state's June 8 primary. Former vice presidential candidate Sarah Palin surprised Tea Party-goers on Thursday by backing Fiorina over DeVore.

President Obama campaigned for Boxer at two fundraisers last month.