Rudy Giuliani has lost his national lead in the Republican presidential race, creating the party's most competitive nomination fight in decades just two weeks before voting starts. A new Wall Street Journal/NBC News poll shows the former New York City mayor now tied nationally with former Massachusetts Gov. Mitt Romney at 20% among Republicans nationally, just slightly ahead of former Arkansas Gov. Mike Huckabee at 17% and Arizona Sen. John McCain at 14%. At a time when Mr. Romney has fallen behind Mr. Huckabee in the leadoff state of Iowa, the result signals a dramatic shift in the nature of the Republican contest: In a party with a history of rewarding established front-runners, there's no longer a front-runner of any kind.