The Illinois Republican voter will be heading to polls Tuesday to decide on their nominee to fight President Obama in November elections.

In Illinois, the latest battleground for the Republican presidential contenders, the fight is between the top two front runners Mitt Romney and Rick Santorum. The opinion polls predict a Romney victory but Santorum hopes that Tuesday's primary results will prove the pre-polls wrong. 

According to the latest Gallup tracking poll, Romney has 35 percent support while Santorum is closely behind with 29 percent followed by Newt Gingrich at 13 percent and Ron Paul at 10 percent of votes polled.

PPP (D) poll, on the other hand, indicates a Romney sweep and has predicted 45 percent support to him while Santorum is at second place with 30 percent support.

Winning the primary is important for both the frontrunners. A convincing win here will help Romney to steady his shaky momentum and to arrest Santorum's surge in the race.

Meanwhile, for Santorum, stakes are even high as he is still struggling to prove his electability among all the sections of the GOP voters. A win here is important to continue his race ahead.

Romney campaigned extensively in state focusing on economic issues, but had to face some tough questions on his healthcare and birth control policy. Meanwhile, Santorum concentrated in highlighting his conservative stands to project himself as the best replacement for President Obama.

Delegates: Illinois has 54 delegates to offer - 3 each from its 18 congressional districts.

Polling Station Information: Illinois GOP voters can find their polling station information here.

Where to Get Live Results: Google will provide Illinois live updates. Unofficial primary results are also available here and here.

Polls start on 6 a.m. and ends at 7 p.m. local time. There is no official party registration in Illinois. Any registered voter may vote in the Republican Primary so long as they are not voting in another political party's primary at the same time.