By Joseph Ax
(Reuters) - Alabama voters will cast ballots on Tuesday for the Republican nominee to fill a U.S. Senate seat in a race that has pitted the party's leaders, including President Donald Trump, against its anti-establishment wing.
Senator Luther Strange, appointed in February to the seat left open when Jeff Sessions became U.S. attorney general, faces off against Roy Moore, an arch-conservative former state chief justice.
Moore finished ahead of Strange in last month's initial round of voting. But Trump, said Strange, whom he endorsed, has the best chance of winning the general election.
"Roy Moore is going to have a very hard time getting elected against the Democrat," Trump told an Alabama-based radio show on Monday. "Against Luther, they won't even fight."
Alabama has not had a Democratic U.S. senator since 1997, and Trump carried the state by a margin of more than 25 percentage points in the presidential election last November.
Trump appeared with Strange at a rally in Huntsville on Friday. The president seemed acutely aware that the race's outcome would be seen as a test of his ability to motivate his base to vote for a party-backed incumbent, rather than a firebrand outsider.
"I'm taking a big risk because if Luther does not make it, they are going to go after me," said Trump, who also vowed to campaign for Moore if he beats Strange.
Senate Majority Leader Mitch McConnell has been one of Strange's most vocal backers, and a political action committee affiliated with McConnell has spent close to $9 million advertisements in the race.
Trump's endorsement came as a surprise to political analysts, given the president's tense relationship with McConnell and Moore's status as the insurgent candidate.
The evangelical Moore has drawn support from a number of anti-establishment figures, including Trump's former chief strategist, Steve Bannon. Trump's housing and urban development secretary, Ben Carson, also backed Moore.
Moore, 70, is best known for losing his position as the state's top judge twice, once for refusing a court order to remove a Ten Commandments monument from the courthouse and a second time for defying the U.S. Supreme Court's decision to legalize same-sex marriage.
Strange, 64, served as Alabama attorney general under former Governor Robert Bentley, who left office in April amid a sex and ethics scandal. Some critics accused the governor of appointing Strange to the Senate to avoid further investigation.
Both candidates have praised Trump and vowed to support his agenda.
The winner on Tuesday will be favored in the December election against Democratic nominee Doug Jones.
(Reporting by Joseph Ax; Editing by Colleen Jenkins and Leslie Adler)