Montgomery, Alabama: Voters in Alabama headed to the polls on Tuesday in a hard-fought US Senate race with high stakes for President Donald Trump, who has endorsed fellow Republican Roy Moore in spite of allegations against him of sexual misconduct toward teenagers.

Moore, 70, a former Alabama Supreme Court chief justice, is battling former US attorney Doug Jones, a Democrat, for the Senate seat. Jones, 63, hopes to pull off an upset victory in the deeply conservative Southern state.

The race will test Trump's political clout after nearly a year in office, with his approval ratings at historically low levels. A win by Moore would strengthen Trump's grip on the Republican Party, some of whose leaders have not backed Moore.

A Jones victory would mean trouble for Trump and his populist political base. It also would narrow the Republicans' already slim majority in the US Senate, possibly making it harder for Trump to advance his policy agenda.

Polls opened at 1300GMT in the Alabama special election for the seat vacated by Republican Jeff Sessions, who became US attorney general. Reuters