Romney quits, McCain leads Republican race

Clinton, Obama seek knock-out blow

WASHINGTON (Agencies)

Hours after rival Mitt Romney bailed out, Senator John McCain kick started his fight for the backing of his foes in the U.S. Republican Party's conservative base, as Democrats Hillary Clinton and Barack Obama set their sights on a trio of presidential primaries on Tuesday.

Addressing the annual gathering of fervent Republican activists, McCain sought to shore up his conservative credentials and allay fears over his stand on some key issues, as he seeks the party's presidential nomination.

"It is my sincere hope that even if you believe I have occasionally erred in my reasoning as a fellow conservative, you will still allow that I have, in many ways important to all of us, maintained the record of a conservative."

With former Massachusetts governor Romney dropping out of the race on Thursday after a slew of poor Super Tuesday showings, McCain's path to the Republican ticket is suddenly a lot clearer.

But recognizing the crucial support he needs from the party's conservative base to win the nomination for the November elections, the Vietnam war veteran called for its backing in defeating the Democrats.

"I am acutely aware that I cannot succeed in that endeavor, nor can our party prevail over the challenge we will face ... without the support of dedicated conservatives."

Peppering his speech with references to former president and Republican icon Ronald Reagan, McCain set out a platform of tough stands on various issues, from abortion to tax cuts and his unwavering support for the Iraq war.

The Arizona senator, 71, has a solid conservative voting record, but has enraged the key constituency with his stands on immigration reform, by initially opposing Bush's huge tax cuts and on campaign finance measures.

But addressing the immigration issue head-on, McCain told the Conservative Political Action Conference (CPAC) that he had "stood my ground aware that my position would imperil my campaign."

Barack vs Clinton

In the other camp, meanwhile, Washington, Maryland and Virginia have become key pawns in an electoral chessboard after Clinton and Obama shared the spoils of Super Tuesday this week, forcing them into a protracted battle for the Democratic nomination.

Virginia is the biggest prize of the lot with 83 delegates, while Maryland counts 70 of them. The U.S. capital, which is not part of any state, offers 15 delegates.

The three primaries are of no consequence to the Republicans since McCain emerged as the likely nominee after Romney dropped out.

But with little separating the Democratic contenders following the 24-state Super Tuesday, Clinton and Obama are campaigning hard for what has been billed as the "Potomac Primary" -- named after the river separating Virginia, Maryland and Washington.

The Democratic senators both have campaign stops in Richmond, Virginia on Saturday, while Obama plans to woo voters in other parts of the southern state on Sunday and Monday.

Before the Potomac Primary, however, the candidates face other contests this weekend in Louisiana, Nebraska, Maine, the northwestern state of Washington and the Virgin Islands.