This mobile anti-Trump ad cruised Maryland’s state capital on Wednesday. (Linda Davidson/The Washington Post)

For more than two weeks, Rep. John Delaney has demanded to know whether Maryland’s Republican governor will back Donald Trump if the billionaire business mogul captures the GOP’s 2016 presidential nomination.

On Wednesday, the Maryland Democrat, who is running for reelection this year in a district that stretches from liberal Montgomery County to more conservative western Maryland, took his campaign to Gov. Larry Hogan’s back yard.

A mobile anti-Trump billboard circled the state house — directly behind the governor’s mansion in Annapolis — challenging Hogan to take a position on the brash-talking Republican front-runner.

One side of the advertisement posed a question for Hogan: “Will you support Trump as the Republican nominee?” The other side was a statement, attributed to Delaney: “Because everyone in Maryland will lose if Trump wins.”

This mobile anti-Donald Trump ad calls on Governor Larry Hogan (R-Md.) to take a stance again the Republican presidential frontrunner. (Josh Hicks/The Washington Post)

Justin Schall, Delaney’s campaign spokesman, said the billboard is part of an effort to portray Delaney as a leader willing to stand up to Trump, who has made controversial remarks about immigrants, women, Muslims and protesters at his rallies and is opposed by a significant segment of the Republican establishment, including 2012 nominee Mitt Romney.

Schall declined to say how much Delaney — a health-care financier who funded his own run for office and is one of the richest members of Congress — paid for the ad. But such efforts typically cost about $1,500 for each day of driving, plus up to $3,000 for production.

“One of the big problems we face is Donald Trump’s hatred and bigotry,” Schall said. Hogan, he added, “should lead. It will take less than five minutes to answer this simple question.”

Hogan spokesman Matt Clark said that Delaney’s effort to corner the governor was misguided.

“No one in Maryland wants to see to the discourse in our state devolve into the chaos and partisanship that has become commonplace among professional politicians in Washington,” Clark said.

“With all of the problems we are facing as a state and as a country, you’d think he’d have better ways to spend his time.”

Schall said that Delaney is hoping to energize Democratic voters in his district, which is more closely divided along political lines than other parts of the state (44 percent of voters are registered Democrats, while 32 percent are registered Republicans).

The two-term congressman — who narrowly defeated a Republican opponent in 2014 — faces a challenger in the April 26 Democratic primary, Tony Puca, who has aligned himself with presidential hopeful Bernie Sanders.

There are several Republicans competing for the nomination to run against Delaney in November’s general election.

The mobile billboard was scheduled to cruise through downtown Annapolis for several hours Wednesday, including along Main Street and at the popular waterfront. Schall said the truck will return Thursday if Hogan does not take a position.

Despite the sunny spring weather, few people were outside the statehouse to see the billboard Wednesday, although a few tourists from China pointed and laughed as it passed.

“We can’t vote here, but it’s very interesting because many people talk about Trump,” Lin Hui said.

Hogan was a vocal supporter of former GOP presidential candidate Chris Christie, the governor of New Jersey, who is a good friend of Hogan’s and was a strong backer of Hogan during Maryland’s gubernatorial campaign.

Christie dropped out of the race last month and later endorsed Trump.

At that point, Hogan said he had no plans to endorse anyone else in the race and was “completely disgusted with national politics in both parties.”