DES MOINES, Iowa (AP) -- An outside conservative group began airing advertisements Tuesday that attack two Democratic lawmakers seeking Senate seats because they voted for the 2010 health care bill and repeated President Barack Obama's now-discredited assurance that people with private health insurance could keep their coverage if they liked it.
The move marks an expansion by Americans for Prosperity, whose roughly $1.8 million in television and radio ads in Iowa and Michigan, add to the string of vulnerable Southern Democrats the billionaire Koch brothers have been trying to weaken as Republicans eye gaining control of the Senate in November's elections.
The group has spent more than $20 million on advertising since the public enrollment of the 2010 health care law began in October. Since then, millions of private policyholders have received cancellation notices and enrollment in the insurance plans offered on state and federal exchanges has run well behind original administration forecasts.
The latest ads target Democratic Reps. Bruce Braley of Iowa and Gary Peters of Michigan.
"President Obama won Michigan and Iowa twice. I think it's telling for his supposed signature accomplishment, that it's even deeply unpopular in these two states," said Tim Phillips, president of Americans for Prosperity, the conservative group founded by billionaire brothers David and Charles Koch.
In December, The Des Moines Register's Iowa Poll found nearly half of Iowans considered the health insurance overhaul "very bad," compared to 10 percent who called it "very good."
The group is also targeting Democratic Senate candidates in Alaska, Louisiana, New Hampshire and North Carolina. Phillips was planning to unveil a new ad in Montana, where Democratic Sen. Max Baucus is not seeking re-election in November, giving Republicans a chance in that GOP-leaning state.
Democrats hold a six-seat edge in the Senate.
Veteran Democrats are also retiring in Iowa and Michigan, where Republicans have governors seeking re-election and are trying to project momentum heading into the midterm election, when the White House's party typically suffers losses.
Braley and Peters did say when they voted for the 2010 health legislation that private policy holders could keep their coverage if they liked it, which turned out to be untrue and resulted in millions of policy cancelations last fall.
Both representatives backed legislation last fall to allow those policyholders to keep their coverage.
Peters said in a recent Associated Press interview that's because he's "a practical problem solver trying to get things done."
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