CBS News: Romney to win Illinois primary CBS News projects that Mitt Romney will defeat Rick Santorum and his other rivals to take the Republican presidential primary in Illinois. The estimate is based on early exit poll results and vote totals. With 18 percent of precincts reporting, Romney had 88,870 votes to Santorum's 44,377. Ron Paul was in third with 14,872 and Newt Gingrich in fourth with 10,934. Live Illinois Election Results CBS News exit polls found that Romney, whose base of support was in Chicago and its suburbs, performed well among men, college graduates, Catholics and voters who see the economy as the most important issue facing the country. He also had a small edge over Santorum among women and those identifying as conservative. Santorum was leading Romney among white evangelicals and those identifying as very conservative. Exit polls found that 43 percent of Illinois Republican voters said Romney is not conservative enough, while an equal percentage said his positions were about right. Forty-six percent said Santorum's positions were about right, while 32 percent said he was too conservative and 15 percent said he was not conservative enough. Illinois Exit Poll Results Illinois primary results by county Romney was backed in Illinois by a massive spending advantage over the other candidates for the GOP nomination, as he has been in other states. Romney and his backers spent more than an estimated $3 million on television ads to Santorum's estimated $167,090. Also boosting Romney was the perception that he has the best chance to defeat President Obama in November. Exit polls showed that 60 percent said Romney was the most electable candidate, compared to 22 percent for Santorum and 10 percent for Gingrich. In the exit polls, Romney led his rivals on the question of which candidate best understands the problems of average Americans, with 35 percent support to Santorum's 29 percent and Gingrich's 19 percent. In the Ohio primary, the wealthy former CEO was at only 22 percent on this question. Romney is now expected to take to take the lion's share of the 54 delegates up for grabs in the primary, which are allocated proportionately. The former Massachusetts governor is focused on getting the 1,144 delegates he needs to clinch the nomination before the convention. His rivals are largely trying to keep Romney from that threshold, with the hope of ultimately securing the nomination at a contested convention. Santorum was not eligible for ten delegates in Illinois because his campaign failed to identify supporters who could serve as delegates in four congressional districts before the election. Neither Gingrich nor Paul seriously contested the state. CBS News estimated that Romney had 493 delegates entering Tuesday, more than his three rivals combined. Santorum had 218 delegates in CBS News estimates, while Gingrich had 120 delegates and Paul had 42 delegates. Santorum said before Election Day that he was holding out hope for a surprise victory driven by the more rural, conservative voters in the southern and western part of the state, saying it would "really send shockwaves" through the Republican establishment. He held four rallies and submitted to 19 interviews in Illinois on Tuesday in a last-ditch effort to spur turnout among his largely-downstate supporters before heading to his home state of Pennsylvania, where voters go to the polls on April 24. Santorum's campaign argued earlier Tuesday that the delegate estimates by CBS News and other news outlets overstated Romney's advantage, since they are doing well in certain county, district, and state conventions that will send delegates to the Republican convention. It also plans to challenge the decision by Florida and Arizona, a pair of states won by Romney, to award delegates in a "winner-take-all" fashion. A successful challenge would reduce Romney's delegate advantage. In addition to Pennsylvania, Santorum hopes to do well in the Louisiana primary on Saturday and go on to win in Arkansas and Kentucky on May 22. He has also set his sights on Texas, which offers 155 delegates and which holds a primary on May 29. In the short term, however, the calendar offers Romney far better opportunities to garner delegates. There are primaries in April in the District of Columbia, Maryland, Wisconsin, Connecticut, Delaware, New York, Pennsylvania and Rhode Island, most of which Romney is expected to win. Santorum's best chance for victories in April come in Maryland and Wisconsin. 2012 Republican Primary Calendar A victory in Illinois would be the third victory in the Midwest for Romney, who attacked Santorum in the run-up to Tuesday's contest as having "the same economic lightweight background the president has." Santorum, who has been hammering Romney over his past support for an individual health care mandate and his past as a "Wall Street financier," shot back that "If Mitt Romney's an economic heavyweight, we're in trouble." The Santorum campaign has argued that if Gingrich left the race it would open the door to Santorum winning the nomination on the strength of conservative support. In exit polls Tuesday, Illinois Republican voters were asked how they would vote if only Romney and Santorum were in the race. Forty-eight percent said they would support Romney, 40 percent chose Santorum, and 11 percent said they would not have voted. In a statement Tuesday night, Gingrich took aim at Romney for spending so much to win and vowed to stay in the race, saying "we need a nominee who offers powerful solutions that hold the president accountable for his failures." Vote counting in Illinois was going slower than expected because the paper ballots used by several counties could not fit in the computerized machines that tabulate vote counts. Some election workers were forced to manually cut down the ballots so that they fit the machines or count votes by hand.