Associated Press

MONTGOMERY, Ala. (AP) - President Donald Trump's political muscles are about to get a workout - in a Republican runoff election in Alabama.

The race has an unusual dynamic: The president is campaigning for the establishment-backed incumbent over an upstart beloved by many of Trump's own supporters.

The president is heading to Huntsville, Alabama, on Friday to stump for Sen. Luther Strange. Strange is locked in a tight race with former Alabama Chief Justice Roy Moore, a jurist who has taken losing stands for the public display of the Ten Commandments and against gay marriage.

Moore has run as an anti-Washington candidate and has the backing of Trump's former chief strategist Steve Bannon. A rally for Moore Thursday night is featuring former Alaska Gov. Sarah Palin and former White House official Sebastian Gorka

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