(CNN) The first significant ad buy for state Sen. Erica Smith, a Democratic candidate for US Senate in North Carolina, appears to be backed by Republicans.

Faith and Power, a new political action committee with ties to Republicans, formally launched on January 29 and spent more than $1.9 million to influence the Democratic primary, according to filings with the Federal Election Commission and the Kantar Media's Campaign Media Analysis Group.

The television and radio ads aims to boost Smith over Cal Cunningham, who has been endorsed by the Democratic Senatorial Campaign Committee and has raised significantly more money.

"Who's the Democrat for US Senate endorsed by progressives and unions? Erica Smith," says the ad's narrator. "Who's got the courage to vote for 'Medicare for All'? Erica Smith. The number one supporter of the Green New Deal? Erica Smith again."

"Erica Smith is one of us -- a high school educator, engineer, state senator and ordained minister," adds the narrator. "Vote Democrat Erica Smith for US Senate, the only proven progressive."

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