Senate Republicans launched an attack ad assailing U.S. Sen. Raphael Warnock for backing a federal voting overhaul on Tuesday shortly after it was blocked by a filibuster, part of an intensifying effort to weaponize the Democrat’s support for the measure ahead of his re-election campaign.

The ad, backed by a six-figure week-long buy, frames the proposal as “welfare for politicians” and calls on Republicans to donate to the National Republican Senatorial Committee to “stop” him from pushing more voting changes.

It was part of a volley of NRSC ads aimed at vulnerable Democratic incumbents. But the 30-second spot targeting Warnock, who grew up in public housing in Savannah, was the only that used “welfare” as a pejorative.

(An ad focused on Sen. Margaret Hassan of New Hampshire billed it as a “Washington waste plan,” while another from a GOP-aligned group hitting Sen. Mark Kelly, a former astronaut, used the phrase “this isn’t rocket science.”)

The powerful group hasn’t backed any candidate yet in the still-developing race against Warnock, who is seeking a full six-year term after his January runoff victory helped flip control of the chamber.

But state and national GOP groups are trying to weaken Warnock as they ready for their own unsettled primary to challenge him. Most big-name Georgia Republican figures have passed on Senate run, leaving Agriculture Commissioner Gary Black as the most prominent GOP candidate in the race.

That could soon change. Former Georgia football star Herschel Walker is teasing a run for the seat, and his soaring name recognition and support from former President Donald Trump would make him the GOP front-runner. Former U.S. Sen. Kelly Loeffler, narrowly defeated by Warnock, is also contemplating a comeback.

The legislation, known as the For the People Act, was pushed by Democrats as a way to undo new restrictive voting laws adopted in Georgia and other Republican-led states spurred by Trump’s false claims of widespread voting fraud.

Warnock centered his campaign on a promise to expand voting rights, and was long an advocate on the issue as the senior pastor for Atlanta’s historic Ebenezer Baptist Church. In a speech on the Senate floor, Warnock cast the measure as an effort to strengthen the nation’s electoral foundations.

“Resist the easy route — the temptation to hide behind Senate procedure — and let’s have a principled conversation in front of the American people about voting rights. Let’s have that conversation right here, right now.”

The voting overhaul was doomed to fail. Despite solid Democratic support, the party fell short of the 60 votes needed to overcome a GOP-backed filibuster. And several key Democrats opposed weakening the rule that set a 60-vote threshold for breaking the filibuster.

The proposal includes provisions that would roll back state voter ID requirements, push the end of congressional gerrymandering and promote new ethics standards. It also expands early voting and smooths the way to cast ballots by mail.

Republicans describe the measure as a federal overreach that chips away at state’s rights and shifts too much power to Democrats. Critics also seized on a public campaign financing program that could pump millions of dollars toward candidates from both parties in high-profile contests, like Warnock’s re-election bid.

The ad highlights that part of the measure, with ominous captions describing the possibility of a “government-funded $campaign$” in 2022.