Romney wins Puerto Rico Republican primary

Mitt Romney won an overwhelming victory over chief rival Rick Santorum in Puerto Rico's Republican presidential primary, but Romney was campaigning in the critical heartland state of Illinois ahead of that state's primary on Tuesday another chance to prove he's the best choice to challenge President Barack Obama in the November election.   

The former Massachusetts governor has been unable to win the hearts of the party's conservative base who distrust Romney for his moderate past positions on important social issues like abortion and gay rights.      

To gain the nomination, Romney must accumulate 1,144 delegates to the Republican National Convention allocated through state-by-state primary elections and caucuses. Romney is on pace to capture the nomination in June unless Santorum or Gingrich is able to win decisively in the coming contests.       

Before Puerto Rico's vote was in, Romney had 501 delegates, more than all of his rivals combined. Santorum stands at 253, former House Speaker Newt Gingrich has 136, and Texas Rep. Ron Paul is at 50, according to an Associated Press projection.       

AP