(CNN) California's Senate approved a bill this week requiring presidential candidates to submit five years' worth of tax returns in order to appear on the ballot, joining 18 other states in a jab at President Donald Trump's refusal to release his tax returns.

The state's Senate passed the measure by a 27-10 party line vote Thursday. The bill now goes to the state's assembly for consideration. It's not clear if California Gov. Gavin Newsom, a Democrat, would sign the bill into law should it make it to his desk.

Newsom spokesman Jesse Melgar told CNN, "with regard to this and all proposed legislation, should the bill reach the Governor's Desk it would be evaluated on its own merits."

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