WASHINGTON (AP) — Republican Donald Trump and Democrat Hillary Clinton are eyeing an opportunity to pull away from their rivals on Super Tuesday. It will be a delegate-rich dash across the country that could accelerate their march toward the general election.

Voters from Vermont to Colorado, Alaska to American Samoa and several states in between are heading to polling places and caucus sites on the busiest day of the 2016 primaries.

The contests come at a turbulent moment for Republicans as they grapple with the prospect of Trump becoming the party's nominee. Rivals Marco Rubio and Ted Cruz are engaged in a frantic effort to stop the billionaire — with Rubio in particular lobbing surprisingly personal attacks — but it's unclear whether they have made their move too late.

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