The radio ad battle in the Eighth District over Medicare continued Thursday, as a conservative group upped the ante with more than $60,000 in ads supporting Rep. Chip Cravaack.

The 60 Plus Association, a self-described conservative alternative to the AARP, is spending about $65,000 on radio ads in the Eighth District backing Cravaack as part of an $800,000 national buy in 39 congressional districts.

That's significantly more money than Democrats spent on the air this week attacking Cravaack over Medicare. The House Majority PAC, a group formed to help Democrats take back the House majority, spent $5,700, and the Democratic Congressional Campaign Committee put $160 into the Eighth.

The 60 Plus ad thanks Cravaack for "voting to protect Medicare," referencing the Republican 2012 budget passed last week. Democrats say that the budget will gut Medicare, while Republicans argue it will save it from going bankrupt. Either way, the budget that passed the House has little chance of becoming law, as it has no chance of passing the Democratic-controlled Senate.

The $65,000 from 60 Plus is nearly as much as the $104,000 the group spent in 2010 for Cravaack — and the election is still more than 18 months away. It's just the latest sign that in 2012 national money is going to flood into the Eighth, a district that never received much outside attention when Jim Oberstar held the seat.

The 60 plus radio ads will run for 10 days in Cravaack's district, a 60 Plus spokesman said.