Montgomery County state Sen. Richard Madaleno at the Young Democrats convention, at the IBEW Local 26 in Lanham on April 1. (Evelyn Hockstein/For The Washington Post)

Maryland Sen. Richard S. Madaleno Jr. (D-Montgomery) won an online gubernatorial straw poll organized by the Anne Arundel County Democratic Central Committee.

Madaleno received 32 percent of the 272 votes cast. Prince George’s County Executive Rushern L. Baker III came in second with 21.7 percent of the vote, followed by Baltimore County Executive Kevin Kamenetz with 12.9 percent.

The poll results, released Sunday, are a boost for Madaleno, who has said he plans to run for the Democratic nomination but has not officially declared.

In April, U.S. Rep. John Delaney (D-Md.) won a straw poll taken in western Maryland during an annual summit of Democratic Party loyalists. Delaney came in fifth in the Anne Arundel County poll with 9.2 percent, behind civil rights activist Ben Jealous, who took 12.5 percent.

Jealous and Baltimore tech entrepreneur Alec Ross are the only Democrats who have formally announced that they will compete for the party’s nomination to challenge popular Republican Gov. Larry Hogan in 2018.

In addition to Baker, Kamenetz and Madaleno, others considering the race are former Maryland attorney general Douglas F. Gansler and lawyer James L. Shea.

The primary is next June.