12:55am Update:
From the Associated Press:

COLUMBUS, Ohio (AP) - Hillary Rodham Clinton Tuesday night stopped Barack Obama from prevailing among groups -- white men and late-deciders -- that she struggled with in the weeks before the Ohio's Democratic primary.

According to exit polls for The Associated Press and television networks, she also maintained her strong connection with women, older voters and blue-collar workers.

Women were a big factor in giving Clinton her biggest primary victory in more than a month.

They voted in proportionately higher numbers than they did in past Ohio Democratic primaries and gave Clinton the edge over Obama, who had a slight edge among men.

Clinton had lost ground to Obama with white women and lower income voters just two weeks ago in the Wisconsin primary where she lost big. But in Ohio, two in three white women backed her.

The Gender Gap
Male: 41%
Female: 59%

Women Vote
Clinton: 54%
Obama: 45%

Men Vote
Clinton: 47%
Obama: 52%

Top Issue Facing Voters
Economy: 58%
Iraq: 19%
Health Care: 19%

Of Those Who Said Economy Is Top Issue
Clinton: 52%
Obama: 47%

Vote By Party
Democrat: Clinton 53%, Obama 46%
Republican: Clinton 45%, Obama 55%
Independent: Clinton 46%, Obama 54%
*Democrats made up 69%, Republicans 9% and Independents 22%*

Of Those Who Said Change Is Top Quality
Clinton: 27%
Obama 73%

Of Those Who Said Experience Is Top Quality
Clinton: 94%
Obama 6%

ANALYSIS
These exit polls appear to give Senator Clinton a very slight advantage; however, until raw vote tallies start to come in, it is too close to call. Geographically, Clinton wins in industrial and rural areas and Obama wins in urban areas. Obama won 60% of voters who said they lived in urban areas. Clinton won 54% of suburban voters and 67% of rural voters. Finally, the vast majority of Ohioans will be happy with either Clinton or Obama. Of those surveyed in these exit polls, 71% said they would be satisfied with Clinton. Meanwhile, 69% said they would be satisfied with Obama.

6:15 p.m. Update

Ohio Vote By Age
Voters under 30: Obama 65%, Clinton 34%
Voters 60 and over: Clinton 67%, Obama 31%

ANALYSIS
These exit polls affirm predictions that Senator Obama must handily win young voters and Senator Clinton must do equally well among older voters. These demographics are at the core of the respective candidates.
Also, Ohioans were asked if trade reduces more jobs than it creates, and 81% of Democrats in the Buckeye State said yes. The economy and NAFTA have become enormous issues in Ohio and may help shape this race.

The Independent Effect
(AP) Early exit polls show independents are a sizable chunk of the electorate in presidential primaries in Ohio, Texas, Rhode Island and Vermont.

In all those states except Rhode Island, Tuesday's primaries were "open," meaning all voters could choose which party's contest to vote in. In Rhode Island, only registered independents could choose between parties.

The surveys for The Associated Press and television networks found self-described independents were about one in five voters in Ohio's Democratic primary, one in four in Texas, a third in Rhode Island and four in 10 in Vermont.

Exit poll results for Republican primaries were available only in Ohio and Texas. In Ohio, independents were about one in seven GOP voters, in Texas one in five.