NOT A single Republican state delegate or senator represents a Prince George’s County district. This unhealthy situation tends to be self-perpetuating: GOP candidates have been so marginalized that few have the money, political base or basic familiarity with state government to mount a credible campaign for office. Lack of competition in turn allows some less-than-stellar Democrats to win election.

Nonetheless, there are some high-quality candidates this year. We’ve tried to focus our attention on them, without making endorsements in every district.

(Identify your legislative district and current representatives by entering your address at ­mdelect.net . See a sample ballot in your district for the Nov. 4 elections by entering your name, date of birth and Zip code at wapo.st/mdprimary .)

District 22: We endorsed all three Democratic incumbents — Tawanna P. Gaines, Anne Healey and Alonzo T. Washington, a rising star in Annapolis — in the June primary. Joining them on the ballot in November is a lone Republican, Lynn White, a lawyer and a single mother who exudes enthusiasm and political potential but lacks the background and policy depth to challenge any of the Democrats, whom we back again.

District 23A: The voters in this House district have a capable representative in the incumbent, Geraldine Valentino-Smith. Her businesslike approach to legislating and focus on juvenile justice have resulted in worthwhile reforms that do not make big headlines but do need a champion.

District 23B: In this two-seat district, Democratic incumbent Marvin E. Holmes Jr., an expert in environmental policy, deserves reelection. Voters have a poor choice for the remaining delegate slot. Democrat Joseph F. Vallario Jr. is an old-school wheeler-dealer whom voters should have already retired. Republican Mike Hethmon, meanwhile, would bring an outsider’s voice to Annapolis, but his hard-line stance on immigration puts him out of step with us — and reality.

District 24: Three solid Democrats — Erek Barron, Carolyn J.B. Howard and Michael L. Vaughn — are running in this House contest. Ms. Howard and Mr. Vaughn are incumbents who should be sent back to Annapolis. Mr. Barron triumphed in one of Prince George’s County’s hottest primaries this year, and rightfully so. He is already a veteran public servant, having worked as a county and federal prosecutor and as a congressional staffer. His expertise in criminal justice will be a fine addition to the House.

District 26: We’ve been critical of the incumbent Democratic senator, C. Anthony Muse, who has opposed marriage equality and in-state college tuition rates for undocumented Maryland high school graduates. Still, he has been an effective advocate for struggling seniors and for financial literacy. And Mr. Muse is clearly preferable to Kelley Howells, a local GOP activist who has had virtually no involvement with state or local issues.