After brutal losses in the past two elections, congressional Republicans have been hoping that the worst is behind them. But, unfortunately for the GOP, yet another large group of their House members has cause for concern based on their weak performance in the recent election.

Of the successful House Republican candidates, 29 fell below 55 percent of the vote, according to near-final but still unofficial election results. Of that group, 20 were incumbents, three defeated Democratic incumbents and the remaining six won contests for open seats that had been held by Republicans. The group is spread across the nation, with five from California, where Republicans this year retained all 19 of their House seats.

Republican strategists contend that their candidates who survived this year should be well-positioned in 2010, when the campaign focus presumably will turn to the Democrats' performance. But few expected at the start of the '08 cycle that so many Republicans would be at risk this time.

What's especially striking about these 29 Republicans is that 23 of them won fewer votes this year than they or their party's candidate received in 2004, as shown in the accompanying table. For 14 of them, the drop was in the double digits. In the worst case, Rep. Jean Schmidt, R-Ohio, was re-elected with 143,287 votes, compared with the 227,102 received by her predecessor, Rep. Rob Portman; she won re-election 45 percent to 37 percent. In Alaska, Rep. Don Young's winning vote total dropped from 213,215 in 2004 to 147,778 this time, when he survived 50 percent to 45 percent, according to the latest results. (Rep. Mario Diaz-Balart, who won 53 percent to 47 percent this year, was unopposed in 2004.)

The vote fall-off for many of these GOP winners was accompanied by a huge increase for their Democratic opponents. For example, the Democratic vote total against Rep. Dean Heller, R-Nev., climbed 70 percent from 2004, while Heller's vote dropped 13 percent from what then-Rep. Jim Gibbons received.

Some of these House Republicans will contend that they suffered from anomalous local conditions, including the weak showing of their presidential nominee, John McCain. Still, these vulnerable districts can expect early attention from GOP leaders, who won't want to suffer another campaign cycle with their "safe seats" suddenly up for grabs.