WASHINGTON — The Campaign Workers Guild on Monday announced the ratification of a collective bargaining agreement with the campaign of writer-activist Laura Moser, who faces a special runoff election against fellow Democrat Lizzie Pannill Fletcher in a potentially competitive Houston congressional district Democrats hope to wrest from long-time Republican control.

The Guild said Moser's is the first campaign in Texas to unionize, and one of only 10 in the country so far.

The contract was unanimously ratified by organizers for Moser, who is running to unseat nine-term Republican incumbent John Culberson in November.

The May 22 runoff has pitted Democrats who believe they can beat Culberson with Fletcher's more centrist message on issues such as health care against those who believe Moser can better mobilize the party's liberal or "progressive" base.

The Democratic Congressional Campaign Committee (DCCC), the campaign arm of the House Democrats, has actively worked to defeat Moser, though it has yet to formally endorse Fletcher in the district, which skews Republican.

For Moser, the union deal plays to the party's labor constituency. In the March 6 primary, Fletcher, an attorney, ran afoul of the local AFL-CIO for her law firm's past work on behalf of employers against a union representing immigrant janitors.

Fletcher said she was not involved in the case. More recently, she said she has been working to repair her relationship with the union.

Moser's move, however, could scramble organized labor's support in the election, considered key to Democratic hopes of winning back control of the House in 2018.

"Progressive campaigns should pride themselves on fighting for workers all over the country," said Julia Doubleday, Deputy Data Director and union steward for Laura Moser for Congress. "And it's crucial that candidates demonstrate their commitment to those values with their own staffs as well. I'm looking forward to seeing other candidates follow Laura's example to support campaign unionization."

According to the Guild, Moser's campaign workers will get benefits like payment for health insurance, paid sick days, and paid leave. The contract also includes a grievance procedure.

"Democrats need to walk the walk when it comes to standing with labor," Moser said.

"Campaign workers are finally getting the same labor protections their candidates are stumping for," said Meg Reilly, Vice President of the Campaign Workers Guild. "Campaign workers for Moser are the first in Texas to unionize, and we're excited to see which campaign workers will unionize here next."