Restore Our Future, a Romney-backing super PAC, plans to spend $14 million in ads in nine states, such as Colorado, Florida and Virginia, in October's final week, Politico reported Friday. That is more than the group spent in September.
Last week, President Obama's campaign spent less than Romney's for the first time since the summer, Politico said. Kantar Media/CMAG estimates Obama ran 28 percent more ads than Romney in the period between the Republican convention and the end of September.
Restore Our Future's treasurer, Charles R. Spies, said his group and other conservative super PACs are "leveling the playing field."
"That effort will continue at an increasing level going forward," he added.
Bradd Todd, a Republican strategist, said the target of the blitz is likely to be voters who are unhappy with the Democratic president but still on the fence.
"Advertising at the end typically makes the biggest difference to those voters," Todd said.
Romney's performance in the first debate also gave his campaign a financial boost, although Obama is also laden with cash after a strong September.