DELRAY BEACH, Fla. – Heading into the campaign’s final weeks, Republican presidential candidate Mitt Romney is upping his criticism of President Barack Obama’s plans for a second term, accusing the Democrat of failing to tell Americans what he would do with four more years.

The Obama campaign is aggressively disputing the notion, claiming it’s Romney who hasn’t provided specific details to voters.

At campaign events, in a new ad and fundraising appeal out Saturday, Romney is setting up the closing weeks as a choice between what he says is a “small” campaign that’s offering little new policy and his own ambitious plan to fundamentally change America’s tax code and entitlement programs.