Rahm Emanuel may claim Chicago's mayoral office on Tuesday

Polls show Rahm Emanuel leading rivals, but it's unclear if he'll have enough support to avoid a runoff.

Polls have shown Rahm Emanuel with a significant lead over his rivals for Chicago mayor, but it's unclear if he'll have enough support to avoid a runoff.

If Emanuel gets above 50 percent in Tuesday's primary, the former White House chief of staff will avoid a runoff election with his nearest rival.

He's been leading Carol Moseley Braun, a former senator; Gery Chico, the former Chicago Public Schools chief; and City Clerk Miguel del Valle, but the margin has varied.

Turnout is expected to be close to 50 percent, which means that it would take support from only a quarter of the electorate for Emanuel to become the city's mayor, ABC7Chicago pointed out.

If no candidate receives over 50 percent of the vote, the top two contenders face off in an April 5 runoff.

Meanwhile, another report found that Emanuel received the majority of his more than $11.9 million in campaign contributions from outside the city. Only $5.38 million came from donors with Chicago addresses and almost 30 percent of his total haul came from out of state, according to the Chicago News Cooperative.

Polls stay open until 7 p.m. CST.

— This post was updated at 9:47 a.m.

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