Washington (CNN) - One of the top non-partisan political handicappers is increasing his forecast of how many seats the Republicans may pick up in the House of Representatives this November.
The Rothenberg Political Report is out with a new prediction Tuesday pointing towards likely GOP gains from 37 to 42 seats in the chamber, up from 28 to 33 seats from their most recent forecast. The Republicans need a net gain of 39 seats to take back control of the House.
The Rothenberg Report adds that larger GOP gains in the 45 to 55 seat range are possible.
"National and local polls continue to show further deterioration in Democratic prospects," says Stuart Rothenberg, editor and publisher of the Rothenberg Political Report. "The next few weeks will be crucial, as Democratic incumbents seek to drive up Republican challengers' negatives and strengthen their standing in ballot tests."
The other leading non-partisan political handicapper, the Cook Political Report, forecasts a net gain of at least 35 seats and possibly as much as 45 seats.
Last week University of Virginia political handicapper Larry Sabato estimated that Republicans would pick up 47 House seats in the midterm elections.
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