By Tim Reid

WASHINGTON, Aug 4 (Reuters) - Polls began closing in Michigan on Tuesday in a Democratic U.S. Senate primary that has emerged as one of the clearest tests yet of the direction of the Democratic Party ahead of the 2028 presidential race.

The contest pits Abdul El-Sayed, a progressive former public health official who has called for ending unconditional U.S. military aid to Israel, against U.S. Representative Haley Stevens, a moderate backed by Democratic leaders and pro-Israel groups.

Polls began closing at 8 p.m. ET (0000 GMT) and will continue closing across the state for another hour.

The race is the latest battleground between progressives and moderates over U.S. support for Israel, an issue that has played out in primaries nationwide this year. But unlike contests in liberal bastions, this is a statewide race in a critical Midwestern swing state ahead of November's midterms — a seat Democrats must win in the fight for Senate control.