When GOP frontrunner Mitt Romney campaigns in South Carolina on Thursday Newt Gingrich will be there on TV calling him "timid."
"Timid won't create jobs and timid certainly won't defeat Barack Obama," says the narrator in the Gingrich spot.
Romney, who is leading in New Hampshire public opinion polls ahead of the Tuesday primary, eked out an 8 vote victory over surging Sen. Rick Santorum in the Iowa caucus earlier this week.
Santorum is surging against the richly funded Romney despite running a grass-roots, low-budget campaign
Gingrich, whose positions on numerous issues are nearly identical to Santorum's, has said the two should form an alliance to ensure Romney doesn't secure the GOP nomination to run against US President Barack Obama this year.
The former House Speaker also vowed to be more forceful in making contrasts with Romney, after getting hit by attack ads funded by a pro-Romney "super PAC" in the run-up to the Iowa caucuses.
The new Gingrich TV ad mimics a full-page ad that ran in the Union Leader, New Hampshire's largest newspaper that called Romney a "timid Massachusetts moderate."
He also called Romney a "liar" in a move that raised the ire of Romney supporters, including Sen. John McCain who said the comment was "inappropriate."
Romney, once considered a shoo-in for the nomination by pundits, finds himself entering a caucus season that is now up for grabs.
The South Carolina primary is Jan. 21.