(Agencies)
Updated: 2008-03-03 08:27

WESTERVILLE, Ohio - Presidential candidates Hillary Clinton and Barack Obama waged a tight campaign fight across Ohio on Sunday two days before crucial voting that could virtually nail down the Democratic nomination or prolong the party battle into the spring.

Democratic presidential hopeful, Sen. Barack Obama, D-Ill., talks with reporters during his flight to Cleveland, Ohio Saturday, March. 1, 2008. [Agencies]

One prominent Democrat worried that extended infighting after the voting in four states on Tuesday could split the party into two camps and give a big boost to the presumptive Republican nominee, Arizona Sen. John McCain.

Victories on Tuesday by Obama, especially in the big states of Texas and Ohio, would give the Illinois senator a major boost toward the Democratic nomination in the November election. Clinton victories, however, would revive her campaign and end Obama's winning streak at 11 contests.

McCain, with dwindling competition from the only other major Republican candidate, former Arkansas Gov. Mike Huckabee, took the day off. A big night on Tuesday could put McCain very close to the 1,191 delegates he needs to clinch the Republican nomination at this summer's party convention.

Polls close in Ohio at 7:30 p.m. EST (0030 GMT on Wednesday) and all voting in Texas will be over at 9 p.m. EST (0200 GMT on Wednesday).

The races in Texas and Ohio are very tight after Clinton held big leads a month ago, according to a Reuters/C-SPAN/Houston Chronicle poll released on Sunday.

Obama led in Texas 47 percent to 43 percent while Clinton led by a statistically insignificant one point in Ohio, 47 percent to 46 percent, the poll showed. The poll had a margin of error of 3.7 percentage points.

Obama, who would be the country's first black president, leads in the race for the 2,025 delegates needed to win the Democratic nomination this summer. Unless Clinton wins by very big margins on Tuesday, he will pick up big chunks of additional delegates while her future would be uncertain.

OHIO'S ECONOMIC WOES

Both candidates concentrated on Ohio. Westerville, a suburb of the state capital of Columbus that once was home to the Anti-Saloon League, became an unlikely political ground zero on Sunday with rallies by both Clinton and Obama.

Clinton, the New York senator and former first lady, stressed her experience against what she describes as her opponent's vacant rhetoric.

Mocking Obama as just a speech-maker and not a person of action, Clinton told a rally, "I've given a lot of speeches in my life, probably, I don't know, hundreds of thousands. Sometimes I finish a speech and people come up to me and say, 'Oh that was so inspiring and wonderful and it made me feel so good."'

"I say, well that's great. But that's just words. Our job is to make a difference," she said.

Obama shot back, saying that Clinton had cast his campaign as based solely on rhetoric, particularly a speech he gave in 2002 when he was an Illinois state senator that opposed the Iraq war. Clinton, who has touted her experience, voted in the Senate to authorize military action in Iraq.

"When it came time to make the most important foreign policy decision of our generation -- the decision to invade Iraq -- Senator Clinton got it wrong ... I don't know where all this experience got her," Obama told a crowd in Westerville.

"And to this day, she won't even admit that her vote was a mistake or even that it was a vote for war. And so besides that decision to invade Iraq, we're still waiting to hear Senator Clinton tell us what precise foreign policy experience ... would make her prepared to answer that phone call at 3 in the morning."

While Clinton, who would be the first woman president, and Obama battled it out, one of their former Democratic rivals, New Mexico Gov. Bill Richardson, was worried the fight might continue past Tuesday.

"The concern that I have is the bickering that took place between those two very fine senators is going on too long," Richardson, who bowed out of the Democratic race early last month, said on CBS's "Face the Nation" program.

Richardson has been the object of attention from both camps since he dropped out because, as one of the top Hispanic office holders in the United States, he could have impact with Hispanic voters, especially in Texas on Tuesday.

"We have to have a positive campaign after Tuesday," Richardson said. "Whoever has the most delegates after Tuesday, a clear lead, should be, in my judgment, the nominee."