03/21/2012 11:21 EDT | Updated 05/21/2012 05:12 EDT

Romney looks to April after Illinois win

Mitt Romney, who inched closer to the Republican presidential nomination with a win last night in the Illinois primary, is now looking ahead to April's more favourable contests to knock out his opponents.

Romney coasted to victory over main rival Rick Santorum on Tuesday in Illinois and pad his already substantial delegate lead in the race to earn the nomination to face President Barack Obama in November's general election.

The state also represented Romney's first clear win over Santorum in a de facto head-to-head race, considering the other candidates, Newt Gingrich and Ron Paul, did not actively campaign in the state.

However, Romney repeated a familiar pattern of the race by having to outspend his rival nearly seven-to-one on advertising in Illinois — much of it in the form of attack ads tearing into Santorum's credentials and career in Washington.

"It's time to say this word: enough. We’ve had enough," a confident-sounding Romney told supporters at his victory night party in suburban Chicago.

"We know our future’s brighter than these troubled times. We still believe in America, and we deserve a president who believes in us, and I believe in the American people."

Meanwhile, Santorum insisted he was not stepping aside, and urged conservatives to back him after he picked up "lot of delegates tonight in a very tough state."

“It wasn’t a tough night; we did very well," Santorum told reporters. “Again, it’s very clear it’s a two-person race and now we need to get all the conservatives to line up behind us.”

Santorum, a staunch social conservative, stepped up his personal attacks on his rival while campaigning in Illinois, declaring Romney "doesn't have a core" and has been "on both sides of almost every single issue in the past 10 years."

If Romney becomes the nominee, expect the Democrats to remember those statements and amplify them.

Santorum looks to Louisiana, Pennsylvania

As in previous contests in midwest states like Ohio and Michigan, Santorum failed to break through in Illinois. His only hope now — along with Gingrich and Paul — is to prevent Romney from winning the 1,144 delegates needed to secure the nomination at the Republican convention in August in Tampa.

While his opponents hope to drag out the race until then and keep the convention open, Romney, a former Massachusetts governor and successful CEO, has his eyes on winning most of April's primaries, starting with Maryland and culminating in northeastern contests in New York, Delaware, Rhode Island and Connecticut.

The demographics of Republican ranks come relatively close to those in Illinois who overwhelmingly favoured Romney over Santorum, while Romney's recognition as a former governor of a neighbouring state will help him.

Santorum is expected to win Saturday's primary in Louisiana and focus on campaigning for the 76 delegates available in the April 24 primary in his home state of Pennsylvania, where he served as a senator for 16 years before being defeated in 2006.

"We’ve got five weeks," Santorum told supporters Tuesday. "Five weeks to a big win."