But, interestingly, the two parties have about the same number.
From CNS, via U.S. Catholic:

With more than three dozen Catholic Democrats voted out of office or choosing not to run in the November election, a decline in the number of Catholics in the 112th Congress would seem inevitable.

But the decrease is not nearly as steep as might be expected, because of the 33 new Catholic Republicans preparing to take office when the 112th Congress convenes Jan. 3.

With one House race still contested as of Dec. 3 — between Rep. Timothy Bishop, a New York Democrat who is Catholic, and Randy Altschuler, a Republican who is Jewish — the number of Catholics in the 112th Congress will be 149 or 150, compared to the 162 senators and representatives who identified themselves as Catholics as the 111th Congress began two years ago.

The latest number is more in line with the 155 Catholics at the start of the 110th Congress or the 109th’s 153 Catholics.

The change since the last Congress means that Catholics will now make up about 28 percent of the members of Congress, compared to 30 percent when the 111th Congress began. But both figures are higher than the percentage of Catholics in the U.S. population — 24 percent.

For the first time in recent memory, the number of Catholic Republicans in the House — 61 — nearly equals the number of Catholic Democratic House members, at 64 or 65. That marks a dramatic shift since the last Congress convened two years ago with a Catholic House contingent of 98 Democrats and 38 Republicans.

In contrast, the Catholic membership in the Senate has remained relatively stable. Among Republicans, four Catholics left and four new Catholic senators were elected, keeping the total at nine. The number of Catholic Democrats in the Senate went from 17 at the start of the 111th Congress to 15 now, but two of the 17 were now-Vice President Joe Biden, who resigned from the Senate shortly after the session began, and Sen. Ted Kennedy of Massachusetts, who died in August 2009.

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