Webster, Mass.-based personal lines insurer Commerce Group Inc. announced today that its shareholders have voted to approve the firm’s acquisition by Spanish insurer Mapfre S.A. for $2.2 billion.

The purchase by the Madrid-based European insurance giant was originally announced on Oct. 30, 2007.

Commerce said 88 percent of the total number of common stock shares entitled to vote had approved the merger and more than 97 percent of the eligible shares were voted.

At present, Commerce and Mapfre said they expect the merger to occur late in the first quarter or early in the second quarter of this year once approvals are secured from regulators in Massachusetts, California, New York and Ohio.

When the merger is completed, each holder of Commerce common stock at the time of the merger will be entitled to receive $36.70 in cash.

In Massachusetts, Commerce is the leading writer of non-life personal insurance lines with a 31.5 percent share of the auto insurance market.

The Commerce Group Inc.’s subsidiaries include The Commerce Insurance Company and Citation Insurance Company in Massachusetts, Commerce West Insurance Company in California, American Commerce Insurance Company in Ohio, and State-Wide Insurance Company in New York.

Mapfre, which started U.S. operations in 1993, in addition to a small Florida unit has a presence in New Jersey and Puerto Rico and operates Road America Motor Club roadside assistance operations throughout the country.

The insurer in total has operations in 40 countries and is the leading insurer in Spain. In non-life insurance, the company ranks as the largest group in Latin America and the tenth largest in Europe.