HARRISBURG - A Republican-drafted plan for redrawing Pennsylvania's congressional boundaries continues to stir controversy in the Capitol, even as House GOP lawmakers rush to push it through before they leave this week for winter break.

The House spent two hours in heated debate Monday over the proposed map for Pennsylvania's 18 new congressional districts, which has been criticized as an attempt by Republicans to protect members of their own party.

Democrats tried every which way Monday to defeat or delay the bill, offering amendments, challenging its constitutionality and fairness to voters, and charging that it was written to benefit incumbents - particularly Republican ones.

They were not successful. The bill is scheduled for final approval Tuesday. Since the Senate narrowly passed it last week, it will be on a fast track to Gov. Corbett's desk for his signature.

"This is by far the worst case of gerrymandering I've seen in my 25 years here," said Rep. Robert Freeman (D., Northampton).

"There is way too much self-interest here," added Rep. Pamela A. DeLissio (D., Phila.). "I refuse to participate in that kind of manipulation."

A new congressional map is required every decade to reflect shifts in population. Because Pennsylvania grew more slowly than the rest of the nation, it will lose a U.S. House seat, dropping to 18 in the 2012 election.

The party that controls the legislative chambers gets to draw the map. Republicans have majorities in both the House and Senate.

The proposed new district for Republican U.S. Rep. Patrick Meehan, in particular, has been singled out as an example of unabashed gerrymandering. Its jigsaw-puzzle shape has raised the ire of Democrats, who allege it was drawn to excise Democratic areas in favor of more solidly Republican ones.

Meehan has been considered one of the more vulnerable House members in 2012, representing a district carried by Democratic presidential candidates John Kerry in 2004 and Barack Obama in 2008.

"This is being done simply to make the Pat Meehan seat a safe Republican seat. Let's call it what it is," said Rep. Greg Vitali (D., Delaware).

Meehan's proposed new district would include parts of five counties: Delaware, Chester, Lancaster, Montgomery, and Berks. Some heavily Democratic towns in Delaware County with sizable African American populations - Upper Darby among them - would be snipped out and placed in Democratic U.S. Rep. Bob Brady's Philadelphia-centered First District.

Brady also would pick up more white Democratic voters along the Delaware River.

Vitali said the irony in the proposed map was that it also made Democratic districts more solidly so, along with making Republican ones safer.

The result, in his opinion, will be lawmakers who will look to appeal to the ideological extreme among their constituencies, rather than strike a middle ground.

"That is what leads to the gridlock in Washington today," he said.

Under the proposed map, Montgomery County would be split among five districts: the Eighth, represented by Michael Fitzpatrick, a Republican; the Seventh, represented by Meehan; the Sixth, represented by Jim Gerlach, a Republican; the 13th, represented by Allyson Y. Schwartz, a Democrat; and the Second, represented by Chaka Fattah, a Democrat, who would pick up Lower Merion.

Also under the proposed map, Gerlach's Sixth District would extend into Lebanon County; Easton would be separated from Allentown and Bethlehem in the Lehigh Valley; and the districts of U.S. Reps. Jason Altmire and Mark Critz, both Democrats, would be combined into a new 12th District in the western part of the state, which could force them to run against each other next year.

Still, despite the changes, some strategists believe the key swing districts in the Philadelphia and Lehigh Valley regions will remain competitive.

Obama won the towns making up Fitzpatrick's newly drawn Eighth District with 54 percent of the vote in 2008. Kerry carried it in 2004 with 50.7 percent, and Sen. Bob Casey (D., Pa.) got 57.8 percent in 2006.

In Gerlach's Sixth District, Obama got 53.5 percent; Kerry, 46.7 percent; Casey, 54.8 percent.

And it appears Meehan's new district will be about as competitive as the old: Obama, 51.9 percent; Kerry, 48.4 percent; Casey, 55.4 percent.

"Did they get a point or two more Republican? Absolutely," said Josh Schwerin, spokesman for the Democratic Congressional Campaign Committee. "But if you do the numbers, they're still the types of seats Democrats can win. They will absolutely be competitive for the next 10 years, no matter what anyone says."

Contact staff writer Angela Couloumbis at 717-787-5934, acouloumbis@phillynews.com,

or @AngelasInk on Twitter.

Inquirer staff writer Thomas Fitzgerald contributed to this article.