In the frantic race for the Democratic nomination, where every delegate counts, states like Hawaii, Wisconsin and Washington are now playing a bigger role in slimming down the race.
Voters line up to cast their ballots in three states on Tuesday.
At stake: 94 Democratic delegates, 56 Republican delegates.
Sen. John McCain, the presumptive GOP nominee, faces a less contentious nomination. He currently has 830 delegates to former Arkansas Gov. Mike Huckabee's 217. McCain needs just 1,191 delegates to clinch the nomination.
For Democrats, the results of Tuesday's contests could help Sen. Barack Obama continue to ride the wave of momentum into the upcoming March 4 Texas and Ohio primaries -- two contests that could be make-or-break for Sen. Hillary Clinton.
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