A final stretch of primaries will showcase a divided Republican party in Arizona, Kansas, Michigan, Missouri and Washington and test the influence of former president Donald Trump.
The first polls close at 8 p.m. ET.
Leave your reactions in the comments as results come in.
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Taegan Goddard
Taegan Goddard is the founder of Political Wire -- which for more than two decades has been one of the nation's most influential political news sites.
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