By Maeve Reston, CNN

(CNN) -- As California Democrat Kevin de León mounts a difficult and expensive quest to unseat incumbent Democratic Sen. Dianne Feinstein, a super PAC has formed to raise money on his behalf.

The new group, A Progressive California, was set up by California Democratic strategists Dave Jacobson and Maclen Zilber in anticipation of de León's announcement, which came via video on de León's website and social media accounts Sunday morning.

The group will be able to help raise unlimited contributions on behalf of de León from labor groups and other Democratic organizations who worked closely with him and have been crucial to his campaigns as a state senator. Those groups now face far more stringent hard-dollar limits if they want to back de León's federal campaign. The super PAC will allow them to play a larger role.

The group's first digital ad, which was obtained by CNN, features an opening montage of President Donald Trump tossing paper towels to Puerto Ricans, withdrawing from the Paris climate agreement and mocking a disabled reporter at a televised rally.

"This isn't normal," the narrator says, adding that the "status quo" in Washington is unacceptable.

"We need bold leaders that will stand up and say enough is enough," the digital ad says over images of de León, who is credited with "leading the resistance against Donald Trump in California."

"We need a fearless leader to stand up for our values in the US Senate," the narrator concludes, without ever mentioning Feinstein. "We need Kevin de León."

Though A Progressive California was formed to help de León, it was set up in the style of the Democratic super PAC Priorities USA Action, which backed Hillary Clinton in 2016 but also helped other Democratic candidates.

In interviews before de León announced his campaign, Jacobson, who is also a CNN political commentator, acknowledged de León's enormous fundraising challenge against Feinstein, who has the ability to self-finance her campaign.

In a joint statement after the super PAC was formed, Jacobson and Zilber said they believed de León could win the backing of a broad coalition of "working men and women, environmentalists, progressives and young people."

"Today's California represents the heartbeat of the resistance against Donald Trump's racist, xenophobic and divisive Washington," Jacobson and Zilber said in their joint statement. "In many ways, Kevin de León has been a warrior on the forefront of the resistance's battle, standing up for working people, the environment, immigrants, equality and health care for all. His progressive, inclusive and compassionate California-driven agenda is desperately needed in Washington."

In an interview earlier on Sunday, Feinstein strategist Bill Carrick said the veteran senator has ramped up her fund-raising efforts and also has the ability to self-finance. At the end of the last fund-raising period, she had $3.6 million in cash on hand.

De León will be starting from scratch, because he cannot transfer money from his state accounts to his federal campaign.