( CNN ) -- In Louisiana , Republican Bill Cassidy is running to retire Democratic incumbent Mary Landrieu . But national Democrats are hoping the GOP lawmaker 's stance on raising the Social Security retirement age will stop that from happening . The Democratic Senatorial Campaign Committee will unveil a new television ad in the Bayou State on Thursday that hammers Cassidy for favoring increasing the age at which retirees can collect Social Security benefits to 70 . At Tuesday 's debate , Cassidy said he did not support changing benefits for those at or near retirement , but suggested that benefits for younger workers would need to be revamped . Landrieu drew a sharp contrast with Cassidy at that meeting , saying the idea of having people work until they are 70 was `` very bad policy . '' The DSCC is reinforcing that message with its latest ad in the hotly-watched race , one of the key battlegrounds for majority control of the Senate this fall . `` When it comes to seniors , Congressman Bill Cassidy has a plan : Raise the retirement age for Social Security and Medicare to 70 , '' the narrator grimly states . The 30-second spot is part of a $ 2.5 million buy and is running statewide . Landrieu 's campaign on Thursday unveiled a new website , 70WillHurt.com , to highlight Cassidy 's stance on Social Security . The Cassidy campaign , meanwhile , accused Landrieu of trying to `` have it both ways '' when it comes to Social Security , pointing out that the Democrat previously expressed support for the Simpson-Bowles deficit reduction report that would have gradually raised the retirement age . A CNN/ORC survey released last month found Landrieu leading Cassidy 43 percent to 40 percent among likely voters , with the other Republican candidate in the race , Rob Maness , pulling nine percent . With no primary , all the contenders for the Senate seat will be on the ballot this fall . If no candidate receives a majority of the vote on Election Day the top two finishers will advance to a December runoff . In a head-to-head matchup , Cassidy leads Landrieu 50 percent to 47 percent among likely voters .
National Democrats unveil new TV ad in Louisiana on Thursday . It hammers Republican Bill Cassidy on raising the Social Security retirement age . The 30-second spot is part of a $ 2.5 million buy and is running statewide . A September CNN/ORC survey shows Landrieu leading Cassidy by three points .