KILLEN, TEXAS, 6 March 2008 — Tuesday’s wins in Ohio, Texas and Rhode Island have given Sen. Hillary Clinton’s campaign new life and ensured that the suspense of her battle with rival Sen. Barack Obama for the US Democratic presidential nomination will stretch on for weeks. Obama’s only victory came in liberal Vermont.

However, Hillary yesterday hinted at the possibility of sharing the Democratic presidential ticket with Obama, but says voters still have to decide the party nominee.

Obama is playing down his losses on Tuesday in three out of four primaries, including the battlegrounds of Texas and Ohio. He stressed that he is still ahead of Hillary in the delegate count.

Meanwhile, Sen. John McCain easily won the Texas Republican primary, Ohio, Vermont and Rhode Island and clinched his party’s nomination. His rival, Mike Huckabee, dropped out of the race Tuesday night and pledged to support McCain’s candidacy.

This marks a remarkable comeback for McCain, after his campaign was all but written off following big setbacks last summer.

The Democratic contest remains on a knife-edge, following Hillary’s Tuesday wins, and all attention now will focus on the high-stakes battle between her and Obama. Each offered Texas Democrats a historic choice — the first woman or the first black candidate to receive a major party nomination for the nation’s top office.

Hillary clinched a robust victory Tuesday in Ohio and a narrow win in Texas.

It was a tough battle, as Hillary, Obama and their supporters — including former President Bill Clinton, other family members and movie stars — campaigned hard across Texas that, for the first time in 20 years, played an important role in selecting a presidential nominee.

But as she vowed to keep campaigning, the slim margin in the Texas popular vote and an additional caucus process in which she trailed made clear that she would not win enough delegates to put a major dent in Obama’s lead.

Even though Hillary picked up victories in three out of four nominating contests on Tuesday, Obama is still likely to retain an overall lead in the number of pledged delegates to the August national convention that will pick the nominee.

That means Hillary may have to push for support from “superdelegates” — party insiders and elected officials who can vote for anyone they want — which raised the chances of a damaging dispute within the party over how the nominee should be selected.

For how long, however, is the subject of intense internal debate within her camp and the Democratic Party. Officially, Hillary is in it for at least another seven weeks, until the April 22 Pennsylvania primary, but some Democratic officials believe she may still be pressured by unpledged convention delegates to drop out, especially if Obama adds to his delegate lead as expected with wins in Wyoming on Saturday and Mississippi next Tuesday. This reflects the recognition that it would be enormously difficult for Hillary to overtake Obama in the pledged delegates chosen by voters in primaries and caucuses.

By some calculation, Hillary would need to win more than 60 percent of the vote in the dozen contests remaining between now and June 7 to catch Obama in pledged delegates — a steep challenge given that, so far, she has won that much in only one state, her one-time adopted home of Arkansas.