The ad, which casts Southerland as a steadfast opponent of Obamacare, will run for three weeks in the congressman’s Panhandle-area 2nd District. The group is spending $160,000 to air the spot, which was first reported by The Hill and announced in a conference call Wednesday.

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Americans for Prosperity, which has been linked to billionaire industrialists Charles and David Koch, has aired a torrent of ads in recent weeks. Since last fall, the group has spent around $4 million in House races and around $15 million in Senate races. The nationwide campaign is unusual because it comes at a relatively early point in the election year. Most groups – Democratic and Republican – typically wait to air ads closer to the election.

Many of the group’s commercials are focused on attacking congressional Democrats. But the Southerland ad is different. It gives a pat on the back to the sophomore congressman, saying that “Florida families need his leadership.”

It’s the second time the organization has offered support for Southerland; it also aired a commercial backing him up in October. Southerland is one of the most vulnerable House Republican incumbents in the country. He’s facing a challenge from Democrat Gwen Graham, a Leon County schools official and the daughter of former Florida Sen. Bob Graham.

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Several weeks ago House Majority PAC, a leading Democratic outside group, aired ads supporting two congressional Democrats who have come under assault from Americans for Prosperity. But much of the conservative group’s assault has gone unanswered from Democrats, who seem determined to save their cash for later.