WASHINGTON - US Republican Presidential hopeful Mitt Romney was on Tuesday night projected to win his party's Illinois primary by Fox News and CNN.

The projection came after exit polls and early polling results showed that he held big advantage over main rival Rick Santorum.

Early polling results showed Romney gained over 50 percent of the popular vote by Illinois' GOP members, and exit poll also showed that he could win comfortably in that state.

The win gives Romney chance to gain significantly from the delegate-rich state.

Except for winning the popular vote, he could get more delegates than the polling numbers indicated, as Santorum was ineligible for some of the delegates at stake after failing to field a full slate.