In her quarter-century in the U.S. Senate representing California, Dianne Feinstein has built a reputation as a bipartisan bridge builder, a collegial member of a legislative body that values seniority and, at least until recently, civility.
But in the Trump era, a reputation like that may be a weakness, especially in California, home of the anti-Trump resistance where Hillary Clinton drew more than 60 percent of the vote last November.
Ending months of speculation about his political future, State Senate President Kevin de León of Los Angeles announced Sunday that he's challenging Feinstein.
In an interview with KQED, de León acknowledged that challenging Feinstein is "akin to taking on the political monarchy, the establishment" and described it as "a David and Goliath battle."
At 50 years old, the firebrand de León will provide a striking contrast to Feinstein. In Sacramento, de León has championed legislation to increase gun control and defend immigrants against harsh treatment by the federal government, including legislation making California a so-called sanctuary state, which Gov. Jerry Brown recently signed to severely limit local law enforcement's ability to cooperate with federal immigration officials.
In a video announcing his candidacy, de León emphasized his family's working class roots and his single, Guatemala-born mother who came to California from Mexico and "worked her fingers to the bone" cleaning houses to provide for the family.
Accumulated clout versus biography
Feinstein, the top Democrat on the powerful Senate Judiciary, can make the case that California can't afford to lose the clout she's collected over the past 25 years in Congress. She announced her long-anticipated decision to run for reelection last week.
Dan Schnur, a former California Republican political operative, said anyone facing an incumbent with Feinstein's stature and leadership on issues like gun control would be extremely difficult to beat.
"That said, if any progressive Democrat is going to mount a serious challenge to Feinstein, it would probably be somebody with the kind of personal and political biography of de León," Schnur said. "He was raised in poverty, his parents were immigrants and he's been a very, very forceful progressive presence in the state legislature."
Democratic campaign consultant Garry South agreed that Feinstein will be formidable, but he predicted de León will match up well against the 84-year-old incumbent.
"He's young, very vigorous, very aggressive, articulate, dynamic and charismatic," South said. "His personal up-by-the-bootstraps story will resonate with many voters."
"I think if you look at his record in the state as a senator and President pro Tem, Democratic voters are going to like that record a lot more than Dianne Feinstein's in the U.S. Senate," South added.
Feinstein also starts out with considerable advantages, including sky-high name recognition, fundraising capacity, relatively positive approval ratings among voters and high profile endorsements from well-known Democrats, including Senator Kamala Harris.
Out of step with Democratic base?
But some Democrats say Feinstein is out of step with a Democratic base that's eager for a more confrontational approach to the Trump administration. De León has already picked up some endorsements from fellow Democrats in the state legislature.
"Right now we have a president who has had California in the crosshairs since day one," de León said. "We have a president who is a threat to our economic prosperity to our progressive values and to our people."
A few weeks ago, de León was highly critical of Feinstein after she said people should give Trump more time.
"The question is whether he can learn and change," Feinstein said before an audience at the Commonwealth Club in San Francisco. "If so, I believe he can be a good president."
De León, who is known around the Capitol by his initials "KDL," told KQED at the time that "we don't have much patience for Donald Trump here in California," adding that "this president has not shown any capacity to learn and proven he is not fit for office. It is the responsibility of Congress to hold him accountable – especially Democrats – not be complicit in his reckless behavior."
A few days later, Trump announced he was rescinding protections for so-called "Dreamers," immigrants brought here illegally as children, reinforcing the impression by some that Feinstein was out of touch with the base of her party.
De León's entrance into the race could encourage other Democrats to run. The primary election in California is June 5, 2018.