Analysis: Romney's focus shifts to fall fight By Rebecca Sinderbrand, CNN April 4, 2012 -- Updated 1011 GMT (1811 HKT) Mitt Romney moves past GOP nomination battle to take on President Obama Romney says Obama is "out of touch," surrounded by staff of "true believers" Exit polls suggest Romney still struggles with conservative voters (CNN) -- While Rick Santorum and Newt Gingrich can sustain their bare-bones insurgent campaigns long enough to fight through the spring, GOP frontrunner Mitt Romney and President Barack Obama have already moved on to the next battlefield. Earlier on Tuesday, less than a day after his campaign released a tough anti-Romney attack ad labeling him as the candidate of Big Oil interests, Obama criticized the former Massachusetts governor by name for the first time this year, taking a swipe at his support for Rep. Paul Ryan's budget plan. Romney himself has turned up the heat in recent days, telling voters the president is personally responsible for high gas prices. After his decisive victories in the Maryland, Wisconsin and the District of Columbia primaries, Romney fired back Tuesday night in a speech that didn't mention any of his Republican rivals. " (Y) ears of flying around on Air Force One, surrounded by an adoring staff of true believers telling you what a great job you are doing -- well, that might be enough to make you a little out of touch," Romney said. Granted, some of the same weak spots that have plagued the former Massachusetts governor throughout the primary season popped up again on Tuesday. Exit polls in Wisconsin, a major swing state this fall, suggest he still hasn't made the sale with some working-class voters, rural voters or evangelicals. One in three Republican primary voters in the state said they wouldn't be satisfied with Romney as the party's nominee. Six in 10 Wisconsin voters looking for a "true conservative" backed Santorum -- more than four times the number who backed Romney. However, all of those issues are possible fall challenges, not potential nomination hurdles. Four in five Wisconsin voters said they think Romney will be the nominee. Romney may have struggled with the state's most conservative voters, but thanks to a relatively low evangelical contingent, he still squeaked out a narrow win over Santorum with that group. Santorum appears to have gained some late momentum with a double-digit advantage among late-deciders. However, it wasn't enough to blunt Romney's momentum as he pivots further from primary season battles to an increasingly likely fall faceoff. April 1, 2012 -- Updated 2121 GMT (0521 HKT) Video: Newt Gingrich has laid off one-third of his staff, but vows to stay in the presidential race. What's he really thinking? March 30, 2012 -- Updated 1836 GMT (0236 HKT) Another major conservative figure backs Mitt Romney, adding to chorus calling for the divisive GOP nomination battle to come to an end. April 1, 2012 -- Updated 0454 GMT (1254 HKT) Video: Presidential candidates Mitt Romney and Rick Santorum address the Waukesha County GOP Lincoln Day Dinner in Wisconsin. March 27, 2012 -- Updated 2154 GMT (0554 HKT) Challengers to Republican presidential front-runner Mitt Romney say they intend to keep battling until the nomination gets settled. March 31, 2012 -- Updated 1055 GMT (1855 HKT) Video: House Budget Committee Chairman Paul Ryan endorsed Romney's bid for the White House. CNN's Paul Steinhauser reports. March 30, 2012 -- Updated 1240 GMT (2040 HKT) Video: Florida GOP Sen. Marco Rubio makes it clear he will not run for vice president and explains why he endorsed Mitt Romney. March 25, 2012 -- Updated 1903 GMT (0303 HKT) After a big win in Louisiana, Rick Santorum said Republicans are showing that Mitt Romney has not locked up the GOP nomination. March 30, 2012 -- Updated 2318 GMT (0718 HKT) Video: President Obama tells a crowd in Maine that the GOP's you're-on-your-own economic policy is a "sign of madness." March 22, 2012 -- Updated 2135 GMT (0535 HKT) President Obama said critics weren't paying attention to increased oil production at home and were lying about the cause of rising gas prices. March 28, 2012 -- Updated 1239 GMT (2039 HKT) Video: Mitt Romney created a whole new controversy after calling Russia our "number one geopolitical foe." Jim Acosta reports. March 22, 2012 -- Updated 0937 GMT (1737 HKT) Jeb Bush endorsed Mitt Romney but a top adviser's televised comment gave his rivals fresh ammo.