Las Vegas -- Newt Gingrich delivered a fiery closing argument here on the eve of Nevada's Republican caucuses, predicting he would win the GOP nomination and taking several swings at Mitt Romney.

The former Georgia congressman vowed to fight for the nomination all the way to Tampa, called Romney "Obama-lite," and challenged him to another debate.

"It isn't good enough for the Republican Party to nominate Obama-lite," Gingrich told hundreds of cheering supporters at Stoney's Rockin' Country, a country music nightclub in Las Vegas.

Romney campaign spokeswoman Amanda Henneberg responded to Gingrich's comments in an email Friday.

“Newt Gingrich’s flailing attacks are the sign of a candidate trying to distract from his own record to save his sinking campaign," she said. "Newt Gingrich would rather make misleading statements about Mitt Romney’s record than tell Nevada voters suffering from the housing crisis why he took $1.6 million from Freddie Mac or why he filmed a climate change ad with Nancy Pelosi that was funded by George Soros.”

Gingrich is sticking to a lighter public campaign schedule for the third day in a row in the Silver State even as he attempts to rebound from a tough couple of days and gain ground on Romney. Gingrich has just two campaign stops planned for Friday, and both were not announced by his staff until Thursday evening. He is set to visit the International Church of Las Vegas for a question-and-answer session with faith leaders Thursday evening. Gingrich made just two public campaign stops in Las Vegas Thursday and just one at a brewery in Reno Wednesday.

Romney has campaign stops planned for three Nevada cities Friday: Sparks, Elko and Henderson. Texas congressman Ron Paul is also campaigning in Nevada, with three events planned for Friday in Pahrump and Las Vegas. Former Pennsylvania Sen. Rick Santorum was scheduled to campaign in Missouri Friday.

The lighter public schedule could reflect Gingrich’s efforts to raise more money behind the scenes to sustain his campaign through Super Tuesday, when Republicans in Georgia and many other states make their picks. Gingrich attended a private fundraiser at the Mundo Mexican church Thursday after speaking to Hispanic community and business leaders there. And he met Wednesday with billionaire casino magnate Sheldon Adelson, a Las Vegas businessman whose family has contributed $10 million to a pro-Gingrich Super PAC.

Gingrich struggled to gain traction this week amid signs his campaign was in disarray. His campaign scheduled and then abruptly canceled a meeting with Nevada Gov. Brian Sandoval Wednesday. A Nevada campaign aide called the embarrassing cancellation a miscommunication.

And Gingrich campaign sources started telling news reporters Wednesday evening that real estate mogul Donald Trump was preparing to endorse Gingrich. Trump endorsed Romney instead Thursday.

Also a new poll shows Romney maintaining a 20-point lead over Gingrich in Nevada, a state the former Massachusetts governor won handily in the 2008 Republican caucuses.

During an interview on Fox News Thursday evening, Gingrich blamed his recent struggles on negative attack ads from Romney’s campaign.

“Negative advertising to suppress votes may be clever,” Gingrich said, “but it is a terrible long-term strategy.”