Romney backs McCain, Obama picks up support

Former Republican presidential hopeful Mitt Romney endorsed erstwhile rival John McCain on Thursday and urged Republicans to unite behind him in a gesture that could help McCain with disgruntled conservatives.

In a tight Democratic race, Barack Obama continued to pick up steam. The first-term senator secured the backing of one of Hillary Clinton's influential black congressional backers while another prominent civil rights leader and congressman openly discussed a possible switch.

Obama also was likely to win one of the most coveted endorsements in organized labor yesterday, that of the Service Employees International Union. Clinton notched a minor, but much-needed victory of her own, winning on Thursday the popular vote in New Mexico's caucuses.

McCain has been the presumptive Republican nominee since Romney dropped out of the race a week ago. Despite his wide lead in the delegate count, he struggled to win over the party's core conservative and evangelical Christian base -- a voting bloc that has so far sided more with preacher-turned-politician Mike Huckabee.

Romney, a former governor of Massachusetts, endorsed McCain at his former campaign headquarters in Boston, and asked his national convention delegates to swing behind the veteran Arizona senator and former prisoner-of-war in some of his kindest words to date about his former rival.

"Even when the contest was close and our disagreements were debated, the caliber of the man was apparent," Romney said, as McCain stood next to him.

While McCain struggled with conservatives, Clinton faced difficulties of a different sort.

With added momentum from his string of eight victories since last Saturday, Obama has a good opportunity to extend his streak with weekend primaries in Wisconsin and Hawaii, his native state.

He secured two endorsements on Thursday and was expected to win another yesterday.

Former Republican Senator Lincoln Chafee, now an independent, endorsed Obama as the best presidential candidate to restore US credibility.

Similarly, the United Food and Commercial Workers, a politically active union with significant membership in the upcoming Democratic battlegrounds of Texas and Ohio on March 4, threw its support behind him.

Clinton, who just a few weeks ago was considered the overwhelming Democratic favorite, has struggled to keep up with Obama.

Even as she rallied to halt Obama's momentum, jabbing at the front-runner and highlighting her economic policies while portraying him as more flash than substance, she endured another blow as one of her superdelegates, Representative David Scott, switched sides.

"You've got to represent the wishes of your constituency," Scott said in an interview on Wednesday in the US Capitol. "My proper position would be to vote the wishes of my constituents."