Gov. Martin O’Malley (D) addressed a cheering crowd of offshore wind supporters Monday night in Annapolis, kicking off a boisterous rally that had hundreds of miniature windmill-wielding citizens forming a glow-in-the dark circle around the State House.

O’Malley urged the crowd to lobby lawmakers on his offshore wind initiative — one of the centerpieces of his agenda — which passed the House of Delegates on Friday and is now being considered by the Senate Finance Committee.

“It’s very, very important that you talk with them and that you ask them to support wind power now,”O’Malley said.

Lawmakers must take up hundreds of pieces of legislation — as well as resolve major differences in the House and Senate tax and spending plans — before they leave Annapolis next Monday.

Maryland Gov. Martin O'Malley (D) addresses a crowd of offshore wind supporters Monday outside the State House in Annapolis, while Del. Heather Mizeur (D-Montgomery) looks on. (Greg Masters/The Washington Post)

Mike Tidwell, president of the Chesapeake Climate Action Network, said it was the first instance in anyone’s memory of demonstrators encircling the State House.

“All we are saying is give wind a chance,” some demonstrators sang as they stood side-by-side on the sidewalk. The circle, which had some gaps, broke up after about 20 minutes.

O’Malley’s bill would add a fee to every Marylander’s monthly electric bill, as well as the bills of large commercial and industrial users, to subsidize development of what could be the nation’s first Atlantic offshore wind farm.

O’Malley argued the plan would create jobs, give the state a competitive edge in a new green-energy market and further his goal of having one-fifth of Maryland’s electricity supply come from in-state renewable sources by 2022.

“It would be absolutely nuts for us, as an Atlantic state, not to want to be one of the first to harness the most available, renewable resource we have out there,” he said.

After last year’s unsuccessful effort to get a bill through the legislature, O’Malley returned this year with a bill that would cap the average monthly cost to residents at $2. But in negotiations with lawmakers, the administration agreed to lower the monthly subsidy charged to residential customers to $1.50, while the fee on nonresidential users was lowered by 40 percent, to 1.5 percent of their electrical bill.

The smaller subsidy could support a 200-megawatt wind farm of about 40 turbines, administration officials said — less than half of what O’Malley sought when he first introduced the idea before last year’s session.