ANNAPOLIS, Md. (AP) -- Some nonprofit organizations say Maryland's estate tax is driving their wealthy donors out of state during retirement. They support a new bill raising the estate tax exemption to $5.34 million per spouse.

House Speaker Michael Busch testified before the House Ways and Means Committee on this bill Wednesday. Miller filed the bill with dozens of co-sponsors.

The federal exemption is $5.34 million, and Maryland's is $1 million.

Opponents -- including Maryland Nonprofits, an organization representing more than 1,400 of the state's nonprofit groups -- say it would cost too much tax revenue.

The Department of Legislative Services estimates tax revenue losses of nearly $138 million annually when the exemption is fully phased in.

A recent study from Phoenix Marketing International showed Maryland has the nation's highest per-capita ratio of millionaires.

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