For Democratic Sen. Dianne Feinstein, complaints from Republicans are a given. But it has to be galling that the sharpest attacks now come from members of her own party.

This week, for example, Democrat Alison Hartson of Orange County, who is running against Feinstein in the June 5 primary, posted a video slamming the senator as a tool of the corporate elite, a wealthy woman taking campaign cash from big-money interests and ignoring the state’s problems.

“Income equality is not the problem for her, it’s the solution,” Hartson says in the spot. “I’m going to get money, and Dianne Feinstein, out of politics.”

That’s a progressive tune that Feinstein, who is seeking her fifth full term in the Senate, is going to hear more and more as the primary approaches. Although there are 12 Republicans on the ballot, none of them poses much of a risk. The most recent report released by the Federal Election Commission showed that as of the end of 2017, the only GOP candidate who listed any contributions had a snappy $130 in his campaign account.

On the Democratic side, though, Feinstein has nine challengers and it’s a safe bet they’re all running to her left.

Hartson, for example, is a former high school teacher who is the national political director of Wolf-PAC, which says its aim is “fighting to end corruption and ensure free and fair elections.”

She’s been endorsed by Justice Democrats, a group formed by former leaders of Vermont Sen. Bernie Sanders 2016 presidential campaign, and has a platform that could be described as progressive plus: Medicare for all, college for all, guaranteed, affordable housing, rent control, a cap on CEO pay and a breakup of big banks.

Then there’s Kevin de León, the Los Angeles state senator, who said at a Washington news conference in January that Feinstein’s “natural inclination is to be anti-immigrant,” and that the former San Francisco mayor should remember “she represents California, not Arkansas.”

Another Democratic candidate, attorney Pat Harris of Los Angeles, has attacked Feinstein for backing increased defense spending, opposing legalization of marijuana and “trying to compromise with Republicans.”

Those progressive attacks haven’t made a dent in Feinstein’s poll numbers. A recent survey by the Public Policy Institute of California found her leading de León, 42 percent to 16 percent, with Hartson and Harris not listed. And none of her opponents has anything resembling the $9.8 million Feinstein has in her campaign account.

But with Feinstein’s opponent in the November runoff almost certain to be a Democrat, her challenges from the left aren’t going away. And that means Feinstein, who has been able to ignore little-known and less financed Republicans in past re-election campaigns, is going to be forced to listen — and probably respond — to what her fellow Democrats have to say.