Mitt Romney may not be the clear frontrunner in the GOP presidential race any more, but that doesn’t mean President Obama’s campaign is going to let up on him any time soon.

Despite Newt Gingrich’s momentum in the GOP race, Obama’s campaign is keeping the focus on Romney, arguing in a memo released today that the former Massachusetts governor’s loss in South Carolina betrays weaknesses in his candidacy and that he’s got a tough road ahead in the Florida primary next week.

“The bottom line is this: the more voters learn about Romney, the more unfavorably they view him,” Obama campaign manager Jim Messina wrote.

Messina pointed to Romney’s drop in the polls and a rise in his unfavorable rating, pointing to attacks on his record at Bain Capital and his refusal to release his tax returns. (Romney finally said Sunday the he would release them Tuesday).

Messina points out that Romney has yet to win any state among independents — though it should be noted that he has finished second among independents in Iowa and New Hampshire to Rep. Ron Paul (R-Texas), whose base of support lies decidedly outside the GOP. He was second to Gingrich among independents in South Carolina

“Romney is now 0-for-3 among independents. But South Carolina’s rejection stands out: It was the first vote in a state where the unemployment rate is higher than the national average, but voters rejected Romney’s profit-at-any-cost record of cutting jobs, wages and benefits while making millions for himself and his Wall Street partners,” Messina wrote.

Messina argued that Romney’s troubles will grow in Florida, which is home to a business, Dade Behring, that lost jobs after being bought by Bain Capital, along with his performance among independents and Hispanics. Messina also said Romney’s support for House Budget Committee Paul Ryan’s (R-Wis.) proposal to overhaul Medicare could hurt him among Florida seniors.

“This week Florida’s voters will meet a candidate with no core values who believes he’s entitled to play by a different set of rules,” Messina wrote “Like their predecessors in the other early states, they will see a career politician willing to say and stand for anything to get elected and is out of touch with working and middle-class Americans.”

Whatever problems Romney might have with independents or other voters, the fact that Obama’s team continues to focus on him reinforces the fact that it sees him as its most formidable potential opponent.

“The last thing the White House wants is Mitt Romney as an opponent – which explains their ‘all hands on deck’ approach for their strategy to ‘kill Romney,’ the same way they engaged in a campaign of personal destruction against Hillary Clinton,” said Romney spokesman Andrea Saul.

Now that Romney is on the downswing, Team Obama appears to be moving in for the kill.