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Ex-Massachusetts governor takes step to challenge Trump for GOP nod

GOP moves to protect Trump in 2020 primaries

Former Massachusetts Gov. Bill Weld announced Friday he has launched an exploratory committee for a possible 2020 primary challenge against President Trump.

Weld is the first person to take a serious step towards challenging Mr. Trump from within his own party. Maryland Gov. Larry Hogan, also a Republican, also hasn't ruled out challenging the president for the White House.

Weld ran for vice president on the Libertarian Party ticket in 2016.

This is a developing story and will be updated.