Final Illinois Republican primary results: With 99 percent of precincts reporting, former Massachusetts Gov. Mitt Romney has 46.7 percent. Former Pennsylvania U.S. Sen. Rick Santorum had 35 percent.
Trailing were Texas Rep. Ron Paul, 9.3 percent, and former House of Representatives Speaker Newt Gingrich, 8 percent.
Gingrich heads to Louisiana Wednesday for four days of campaigning in that state, which holds its primary Saturday. Romney plans a visit to Arbutus, Md., a blue-collar Baltimore suburb.
Santorum plans three days of campaigning in Louisiana, starting Wednesday, while Paul plans two town hall meetings in Louisiana later this week.