Voters across 16 states will cast their primary ballots today -- "Super Tuesday" -- marking the largest Election 2000 event on the political calendar thus far.
Today's elections could have a significant impact on both parties' nominations process because candidates will have the opportunity to win a large number of delegates needed to secure their party's nomination -- and both underdogs need crucial wins to boost their sagging momentum and stay alive in the race.
Much of today's media attention will surround the primary races in California and New York because they have the most delegates at stake.
They will also be the sites of today's most interesting races because polls show the races are the closest there with a large number of undecided voters, according to government Professor Lynn Vavreck, who specializes in campaigns and elections.
Democratic Presidential candidates former Senator Bill Bradley and Vice President Al Gore will vie for 367 delegates in California and 243 in New York. Republican Presidential candidates Governor George W. Bush, Senator John McCain and former U.N. Ambassador Alan Keyes stand to gain 162 and 93 delegates in those states respectively.
"I think McCain can pull it out in some places he's not expected to do very well, especially in California and New York," Vavreck said.
She said McCain and Bradley need to win at least two significant states. She added that wins in just New York and in New England will not be sufficient, but pulling either Ohio, Georgia or California away from the frontrunners would be necessary.
"McCain needs to do incredibly well in New England and show he can win outside there," government professor Constantine Spiliotes said.
"Gore will do well, but the question is how quickly Bradley will get out of the race. It will be surprising if Bradley stays in past tomorrow," Spiliotes said.
"The Democratic races [today] seem to be major blowouts for Gore, and there is no reason for Bradley to make that [difference] up in the next 24 hours," Vavreck said.
Similar to South Carolina, Southern states like Georgia and Missouri are solid Bush territory because voters are more conservative and religious, she said, adding McCain should do well with more liberal New England voters.
Spiliotes said he liked McCain's chances of doing better than expected in today's primaries over Bradley's upset chances.
"It's hard to tell. [McCain's] been down before so you can't write him off," he said.
Peculiarities in the California and New York primaries will add to the excitement of the races. In California, winning the popular vote does not automatically translate into winning delegates, Spiliotes said, noting that Bush may take all the delegates but place third in the popular vote.
In that primary, any voter, regardless of affiliation, can vote for a candidate in either party, but the ballots are coded so only votes coming from registered members of the party will count in allocating that party's delegates.
New York voters will be voting among delegates rather than the candidates they represent. Spiliotes said Bush has some high profile political names listed for him and that people would be more likely to recognize those names than delegates supporting McCain.
Additionally, Ohio will be closely watched because it constitutes the third largest delegate state in tomorrow's primary frenzy, with 146 Democratic delegates and 69 for the Republicans.
New England will host much of the Super Tuesday political action, with primaries in Connecticut, Maine, Massachusetts, Rhode Island and Vermont where 207 Democratic and 102 Republican delegates will be apportioned.
In other areas of the country, Georgia, Missouri and Maryland will hold primaries where Bradley and Gore will vie for 220 delegates and the Republicans will do the same for 120 delegates.
To round out today's primaries, Hawaii, Idaho and North Dakota, Washington state and the American Samoa will hold Democratic caucuses totaling 132 delegates while Republicans will vie for 59 delegates in Minnesota and Washington caucuses.
Poor showings on the parts of Bradley, McCain or Keyes could prove to be a death knell for these challengers, capping what has been a competitive primary season.
The Republican race has featured many twists in addition to Bush and McCain winning earlier primaries in an alternating pattern.
Bush's campaign did not expect to run to the right, but now that McCain has pushed Bush there, the question will be if he can move closer to center for the general election, according to Spiliotes.
Bush has whittled his once unprecedented war chest so that now neither candidate has an advantage, Vavreck said.
"The media seem to be interested in McCain," she said. "He seems to get coverage whether he wins or loses."
In contrast, "the Democratic race started out really promising and it has really diminished. It's been a combination of Gore getting his footing and Bradley loosing his," Spiliotes said. "Bradley just lost his momentum."
