Former President Barack Obama announced his support Friday for Sen. Dianne Feinstein’s re-election bid, calling her a partner in his work and an effective champion for progress.

Feinstein has “always been an indispensable leader for California, and we became dear friends and partners in the fight to guarantee affordable health care and economic opportunity for everybody; to protect our planet from climate change, and our kids from gun violence,” Obama said in his endorsement message. “I ask Californians to join me in supporting Dianne Feinstein’s re-election and returning one of America’s most effective champions for progress to the Senate.”

Obama’s “effective” comment is exactly the message Feinstein is trying to get out to combat complaints from progressives that she is too moderate and too willing to compromise with President Trump and other Republicans.

Los Angeles state Sen. Kevin de León, a fellow Democrat who is challenging Feinstein, has argued that all-out resistance is the only way to deal with Trump and that the 84-year-old former San Francisco mayor is out of touch with a younger, more liberal California.

Feinstein held out Obama, an icon for Democrats, as an example of what she wants to see in a president — and the model she will follow if she wins re-election.

“President Obama had the grace, wisdom and even-handedness that we quickly came to expect from a president — and that we’re now so sorely disappointed by its absence,” Feinstein said in a statement. “I’ll do my level best every day to build on President Obama’s accomplishments and carry his torch forward, no matter the obstacles that stand in our way.”

Polls in the Senate race have consistently put Feinstein comfortably ahead of de León and a pack of little-known Republicans in her bid for a fifth six-year term. She has the backing of most big-name Democrats, including Gov. Jerry Brown, Sen. Kamala Harris, former Sen. Barbara Boxer, House Minority Leader Nancy Pelosi and former Vice President Joe Biden.

The top two finishers in the June 5 primary will advance to the November general election.

De León did get some good news Friday when La Opinión, one of the nation’s most influential Spanish-language newspapers, announced its support.

“We believe that Kevin de León, more so than Feinstein, is capable of waking up our youth and energizing Latinos to take part in the process that determines their lives,” the paper said. “We believe de León’s trajectory has prepared him to serve in the United States Senate, where he would be the right person at this moment in history.”

John Wildermuth is a San Francisco Chronicle staff writer. Email: jwildermuth@sfchronicle.com Twitter: @jfwildermuth