NEW YORK (TheStreet) -- Pepco Holdings (POM) stock is advancing 27.73% to $27.13 on heavy trading volume on Wednesday afternoon after the company gained the last regulatory approval needed to be acquired by fellow utilities company Exelon Corp. (EXC)

Shares of Exelon are up 0.06% to $35.02 this afternoon.

The D.C. Public Service Commission approved the deal after rejecting two previous proposals, the Washington Post reports.

Chicago-based Exelon agreed to buy Washington, DC-based Pepco in April 2014 in a transaction valued at $6.8 billion. The deal creates the largest publicly-traded utilities company in the U.S., the Post added.

The transaction is expected to close by the end of the month.

So far today, 19.52 million shares of Pepco have exchanged hands, compared with its average daily volume of 3.66 million shares.

Separately, Pepco has a "buy" rating and a letter grade of B at TheStreet Ratings because of the company's revenue growth, compelling growth in net income, good cash flow from operations, impressive record of earnings per share growth and notable return on equity.

You can view the full analysis from the report here: POM

TheStreet Ratings objectively rated this stock according to its "risk-adjusted" total return prospect over a 12-month investment horizon. Not based on the news in any given day, the rating may differ from Jim Cramer's view or that of this article's author. 

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