WASHINGTON, July 25 (Reuters) - A plan to repeal and replace Obamacare that Senate Republicans have been working on for months failed to get the 60 votes needed for approval Tuesday night.

The vote was 43 in favor and 57 against. Nine Republicans voted against the measure.

The plan would have made deep cuts to Medicaid, the health insurance program for the poor, and reduced Obamacare subsidies to lower-income people to help them defray the cost of health insurance.

It was the first of many expected votes this week on repealing or replacing elements of President Barack Obama's signature healthcare law.

(Reporting by Susan Cornwell; Editing by Leslie Adler)