Crummy weather.

Snow and ice are forecast in the north. Heavy rain is expected in the south, where a flood watch has been issued.

"Bad weather in Ohio could make a difference in the presidential nominee," said Peter A. Brown, assistant director of the Quinnipiac Polling Institute. "We'll see how dedicated voters in the two camps are … whose supporters are more committed, and who's willing to get wet."

Brown was in town to declare that his poll showed Sen. Hillary Clinton with a 4-point lead in Ohio, which was pretty much the consensus of late polls -- although one gave a 2-point edge to Sen. Barack Obama.

Republican Sen. John McCain is looking to today's vote to provide him with the 101 delegates he needs to mathematically clinch his party's nomination. Otherwise, the Ohio action has been all on the Democratic side, and it got hotter at the 11th hour.

Clinton, campaigning yesterday in Toledo, accused Obama of being duplicitous about his opposition to the North American Free Trade Agreement. She said Obama was telling Ohio voters one thing while a campaign adviser was assuring the Canadian government not to worry.

Obama has been hammering Clinton in mailers and radio ads on the issue, pointing to positive comments she made in the past about NAFTA. Both candidates say they would renegotiate the deal to add tougher protections for workers and the environment.

Yesterday, Clinton pointed to a report suggesting that despite Obama's public position, his senior economic policy adviser privately told Canadian officials to view the debate in Ohio over trade as "political positioning," according to a memo obtained by the Associated Press. The adviser says he was mischaracterized.

"I don't think people should come to Ohio and tell the people of Ohio one thing, and then have your campaign tell a foreign government something else behind closed doors," Clinton said in Toledo. "So that's the kind of difference between talk and action that I've been pointing out throughout this campaign."

In a phone interview yesterday with The Dispatch from San Antonio, Obama said Clinton's allegation is false, and the matter is a "non-story I think the Clinton folks are pushing because Sen. Clinton has been inconsistent" on NAFTA.

He said his senior economic adviser, Austan Goolsbee, met with Canadian embassy officials at their behest, and "NAFTA was just a side note in the conversation in which he confirmed the position we've taken, which is that we think the labor and environmental agreements need to be amended."

Even so, Clinton suggested that if the story had raised questions about one of her advisers in the same situation, the media would pursue it more aggressively -- a common criticism from her camp in recent weeks.

"I would ask you to look at this story, substitute my name for Sen. Obama's name, and see what you would do with this story," Clinton said.

Her aides called the flap "NAFTAgate," and her campaign hurried a 60-second radio spot to Ohio stations alleging: "As Sen. Obama was telling one story to Ohio, his campaign was telling a different story to Canada."

With analysts saying Clinton must win Ohio to remain viable, she campaigned tirelessly in the state in the past week, tracing the Ohio River on a bus tour in Appalachia and making stops in northern Ohio this past weekend.

As Obama campaigned in Texas yesterday, Clinton had Ohio to herself. She started in the dark by greeting workers at Chrysler's Toledo North Assembly Plant, which makes the Jeep Liberty and Dodge Nitro, at the 6 a.m. shift change.

When asked about her prospects in today's primaries, all Clinton would say is that she's been around many elections and expects to "do well" -- and that she expects the campaigning to continue.

"I think I know what's happening, and I believe that we'll do well tomorrow, and I believe that that's going to be a very significant message to the country," Clinton said. "And then we move on to Pennsylvania and the states still ahead. I'm just getting warmed up."

Referring to the Ohio primary, Obama said: "At this point, I think this thing is too close for anybody to really know exactly what's going to happen."

But Obama suggested he could better weather losses in Ohio and Texas because of his 109-delegate lead.

"Ohio and Texas are very important, but no matter what happens Tuesday, we still have a sizable lead in those delegates," he said. "It's going to be hard for Sen. Clinton to cut deeply into that lead. That's the math."

Numbers, as in turnout, may be key today, and it's also possible the weather might not affect turnout much. In the the 2004 general election, some voters waited in line outside the polls for hours -- in pouring rain. But this year, many already have voted by absentee ballot.

Franklin County has seen a record number of absentee voters for a primary, with 3,000 voting at the Board of Elections yesterday. The Board of Elections stayed open four extra hours, to 9.

Dispatch Washington Bureau Chief Jonathan Riskind contributed to this story.

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