In most years, a successful primary challenge to a sitting House Democrat seems like a longshot. But in Maryland, the expected decision of Prince George’s County State’s Attorney Glenn Ivey to challenge Rep. Donna Edwards might be one worth watching.

Edwards herself was one of those rare successful primary challengers last cycle, sending Rep. Albert Wynn to an early retirement.

Ivey appears to have a better résumé and base of support than your average primary challenger, and as a first-termer, Edwards hasn’t had much time to build a record or get the district used to supporting her. Add up a strong anti-incumbent mood in the suburbs of Northeastern states lately, and this seems to be the year we’re most likely to see a relatively moderate challenger knock off a relatively liberal incumbent in a Democratic primary. Ivey’s chances probably aren’t much better than 1 in 3, but it’s a race worth keeping an eye on . . .