If there’s been one consistent sign of Democratic optimism this cycle, it’s the unprecedented number of Democrats interested in running for Congress.

Candidates keep announcing, and in many more districts than Democrats have targeted before. But in some of these races, there’s already been a Democratic candidate, or ten, for months.

That’s the situation in Florida’s 27th District, an open seat that turned into one of the Democrats’ best pickup opportunities when GOP Rep. Ileana Ros-Lehtinen announced she wouldn’t seek re-election. Five Democrats in the race ended 2017 with at least $300,000 in the bank. This week, Donna Shalala, a Cabinet secretary under former President Bill Clinton, is getting in the contest.

In addition to at least one big-name candidate, others who have local name recognition because they’ve run in the past or already hold a local office are jumping into Democratic primaries. That could shake things up in yet-to-be-determined ways.

In California, a two-time Democratic nominee recently reversed his decision not to run again. Beekeeper Michael Eggman is giving the existing Democratic field some more competition, likely hoping that name recognition on the ballot will give him a leg up.

And in Kentucky’s 6th District, first-time candidate Amy McGrath made a big splash with a viral video that touted her military background and helped her outraise GOP Rep. Andy Barr in the first few months of her campaign. But four months later, Lexington Mayor Jim Gray heeded party calls for him to get into the primary.

Watch: More 2018 Candidate Videos Worth Watching

Cabinet credentials

Shalala officially announced her candidacy in a video on Wednesday.

“Some time ago, I was asked to consider running for the United States Congress,” Shalala says in the video. She says she never expected to run but goes on to describe how President Donald Trump’s agenda energized her.

Shalala’s team conducted polling in January. She took 24 percent in the Bendixen & Amandi poll of 600 likely Democratic primary voters, while state Sen. José Javier Rodríguez received 10 percent. Six other candidates came in at less than 5 percent, with half of respondents undecided or unable to answer. The poll was conducted Jan. 20-24 in English and Spanish with a margin of error of plus or minus 4 percentage points.

“It’s unfortunate for the candidates who have been running for months, to have a big name come in and upend the field,” said one Democratic strategist who’s not involved in the race.

“There are talented rising stars in Miami politics who have been waiting for Ros-Lehtinen to leave, and now they are in danger of being eclipsed again, this time by someone in their own party,” the strategist added.

Shalala’s campaign is playing up her experience and casting her as the candidate who can “make things happen on day one.”

The former Health and Human Services secretary stepped down as president of the Clinton Foundation last spring. In a race where many candidates are already raising serious money, Shalala would bring a strong donor network. Her 14-year tenure as president of the University of Miami makes her a local name, although her time there is also the source of some controversy.

Even before Shalala became a candidate, former circuit court judge Mary Barzee Flores, who has the backing of EMILY’s List, came out swinging against her.

In an early February Medium post, Barzee Flores went after several aspects of Shalala’s career, including her service on (and compensation from) the board of UnitedHealthcare and her response to a hunger strike by janitors at the University of Miami trying to unionize.

At the time, a university chaplain called Shalala an “enemy of the working poor.”

“Our next member of Congress should fight for fair wages and affordable health care, not undermine them,” Barzee Flores said in a statement Tuesday.

State Rep. David Richardson has raised the most money in the primary. His team welcomes Shalala’s entrance as a boon to his campaign, since they see her as a foil to his “Medicare for All” platform. Richardson released a video Wednesday morning — complete with a press release identifying her as an “Ohio native” — that criticized her for not fighting for Medicare for All.

“The people of our district want a bold, progressive champion who is not afraid to challenge the status quo. What they don’t want is a ‘Donna-come-lately,’” Richardson says in the video.

Shalala pollster Fernand Amandi maintains that she’s always supported “universal access for affordable care.” Responding to attacks against her, he praised her for negotiating higher wages for University of Miami employees and raising money for health care clinics in the district during her service on UnitedHealthcare’s board.

If elected, Shalala would be among the oldest first-term members.

“Her age is just a number,” Amandi said. “She’s got great genes.”

National Republicans have struggled to recruit a viable candidate here. National Democrats are confident enough in the fundamentals of the district — Clinton carried it by 20 points — that they’re less concerned with the outcome of the late August primary than they might be in some other races with crowded fields.

“This is a district any of those Democrats will win,” one national Democratic strategist said. Inside Elections with Nathan L. Gonzales rates the general election race Leans Democratic.

The field may still not be settled. It could grow before the May filing deadline. Legislation requiring state and local elected officials to resign their offices to run for higher office could narrow the field too.

Repeat contenders

At the end of last year, three Democrats with at least $100,000 in the bank were running against Rep. Jeff Denham, the California Republican elected to the 10th District in 2010.

Venture capitalist Josh Harder had raised the most money of all the Democrats, ending 2017 with nearly $675,000.

It’s a district Clinton carried by 3 points, but the 2016 Democratic nominee, who was also the 2014 nominee, fell short of knocking off Denham. And now he’s back. Eggman announced in January that he was entering the race, explaining that he’d been asked to reconsider his decision not to run in 2018.

While Eggman is hardly a national figure like Shalala, he has name recognition in the district from his previous runs that could siphon off Harder’s support and complicate Democrats’ efforts to finish in the top-two primary on June 5.

In Kentucky, Gray also lost his last federal campaign, falling to GOP Sen. Rand Paul in 2016. But he actually carried the 6th District in that race, and national Democrats were eager for him to run.

But his entrance incensed McGrath supporters.

“The idea that the national Democratic Party, leadership at the highest level, would say ‘no, we want the establishment candidate with high name ID that can write a check’ says that they haven’t learned any lessons from the last three elections,” Mark Nickolas, McGrath’s campaign manager, told the Lexington-Herald Leader.

McGrath outraised Barr after first getting in race, but Gray outraised her in the last quarter of 2017. The primary is on May 22.

Watch: Gun Control Brewing as Issue in Some Democratic Primaries

Correction: An earlier version of this story identified Mary Barzee Flores as a former federal judge. She was nominated for a federal judgeship but Sen. Marco Rubio blocked her nomination.