These are the candidates running against vulnerable congressional Republicans in the Central Valley

Republicans in Congress from the Central Valley are used to being Democratic targets. Hillary Clinton in 2016 won both of the districts that are considered pickup opportunities in the Democrats’ quest to retake control of the U.S. House.

Here’s a quick look at the candidates who will appear on the June 5 primary ballot in the 10th and 21st congressional districts, and the designations that will be listed after their names.

10th Congressional District

Rep. Jeff Denham has drawn a slew of well-funded challengers. Prior to entering Congress, the Republican owned an agricultural packaging company and almond orchard. Denham voted for the GOP tax plan and to repeal the Affordable Care Act but has pushed his party repeatedly to complete an overhaul of federal immigration policy.

The Turlock Republican was first elected in 2010 and won reelection in 2016 with 51.7% of the vote. That year, Clinton narrowly won the district with 47.4% of the vote.

The 10th district includes all of Stanislaus County and the southern third of San Joaquin County, as well as Modesto, Tracy and Turlock. It is dependent on agriculture and is among the poorest areas of the state.

The ballot:

Denham, Republican, “Businessman/Farmer/Representative”

Michael J. "Mike" Barkley, Democrat, “Lawyer/CPA/Programmer”

Barkley, 73, of Manteca, is making his fourth bid for the seat. He says he was inspired to run for Congress to address gun violence.

Michael Eggman, Democrat, “Farmer/Businessman”

Eggman, 54, is back for a third run at the seat even after saying he wouldn’t try again. The beekeeper and farmer lost to Denham by 3.4% in 2016.

Josh Harder, Democrat, “Educator/Businessman”

Harder, 32, is a former venture capitalist who has raised the most money among challengers. Harder moved back to the district, where he grew up, from San Francisco last spring after leaving his job as a vice president at Bessemer Venture Partners, where he focused on investment in software, mobile and telecommunications.

Ted D. Howze, Republican, “Veterinarian”

Howze, 51, of Stockton, entered the race at the last minute, causing some worry that it would set up a Republican-on-Republican general election race under California’s top-two primary system.

The former Turlock city councilman told the Mercury News he did not know so many Democrats were challenging Denham and did not enter the race to keep a Democrat from getting onto the general election ballot.

Virginia Madueño, Democrat, “Valley Water Commissioner”

Madueño, 52, of Riverbank, entered the race because of Denham’s vote on the GOP healthcare bill last spring. She ran unsuccessfully for the state Assembly in 2016 after serving on the Riverbank City Council from 2005 to 2012, including a stint as mayor from 2009 to 2012. She runs a communications firm.

Dotty Nygard, Democrat, “Registered Nurse”

Nygard, 61, of Tracy, has a nursing degree from Cal State Hayward. She served on the Riverbank City Council from 2010 to 2013. But she’s actually not running: Nygard issued a statement withdrawing from the race after filing to be on the primary ballot. It was not clear Saturday whether her name can be removed without legal action.

Scott Shoblom, no party preference, “Attorney”

An independent, Shoblom, 53, of Modesto, graduated from Empire College School of Law. He was admitted to the California Bar in 2004.

Sue Zwahlen, Democrat, “Nurse/School Boardmember”

Zwahlen, 63, of Modesto, is an emergency room nurse who said she wants to focus on healthcare and education. She has been elected twice to the Modesto City Schools Board of Education.

21st Congressional District

Rep. David Valadao has drawn just a single opponent as he seeks a fourth term. A longtime dairy farmer, the Hanford Republican served in the Assembly prior to entering Congress, where he has focused on bringing water to his agricultural district.

He has been a reliably conservative vote in Congress, supporting the tax bill overhaul and repealing the Affordable Care Act, but he has broken with party leaders on immigration policy. He has advocated for a legislative fix to address the legal status of people brought to the country illegally as children.

Valadao was first elected in 2012 and won reelection in 2016 by a 13% margin in the district, which includes parts of Fresno, Kern, Kings and Tulare counties.

The ballot:

Valadao, Republican, designation not released

TJ Cox, Democrat, “Engineer/Small Businessman”

Cox founded Central Valley NMTC Fund, an organization that invests millions in public and private funds in economically disadvantaged Central Valley communities.

Born in California but raised in Nevada and New Mexico, Cox moved to Fresno with his family in 2000. He originally planned to run in the crowded 10th District race, but switched districts after Democratic lawyer Emilio Huerta dropped out days before the filing deadline.