Low poll ratings for Congress and President Bush,  scandals and history favor Democratic gains in the 2006 midterm elections. While the small number of competitive seats favors Republicans’ retaining their majority, a large national wave for Democrats could bring more seats into play.

To get to the magic number of 218, Democrats need to gain only 15 seats, and five of the past 10 congressional election cycles have seen a swing of at least 15 (1994, 1984, 1982, 1980, 1978). The question for the 2006 election is whether the weakness of Republicans will be large enough to overcome the dearth of competitive seats.

The standing of Republicans is not much better than that of the Democrats of 1994. Then, President Clinton stood in the low 40 percent range for job approval, as President Bush does today, and congressional approval was about 20 percent, compared to a slightly higher but still abysmal 30 percent for the 109th Congress. Mix in all of the scandals, and factor in the likelihood of significant additional revelations from the Jack Abramoff investigations, and Republicans should watch out.

While Republicans’ troubles are significant, Democrats will have to reach deep into Republican territory to gain control of the House. Here are the seats they will need to win:

•Open seats. There are 20 open House seats (excluding the vacant Chris Cox (R-Calif.) and Duke Cunningham (R-Calif.) seats that will be filled by special election). Of these, 13 are held by Republicans, and only six by Democrats (and one by independent Bernie Sanders [Vt.]). Two Republican districts, those of Jim Nussle (Iowa) and Bob Beauprez (Colo.) (both running for governor), voted for John Kerry in 2004 and are especially rich targets for Democrats. Jim Kolbe (Ariz.) and Henry Hyde (Ill.) are vacating swing seats, which voted 53 percent for Bush. If Democrats look further, they find the open seats held by Michael Bilirakis (Fla.), Mark Green (Wis.), Katherine Harris (Fla.), Mark Kennedy (Minn.) and Jim Gibbons (Nev.), whose districts Bush won with 55 to 57 percent. On the Democratic side, the only very competitive open-seat district is Ted Strickland’s (Ohio), which Bush won with 51 percent. In the current open seats, Democrats should expect to net a gain of at least three seats and up to six if there is a big Democratic national trend. There could well be five or six more open seats by the spring and possibly even more if the Abramoff scandal revelations force an even larger number to retire. The Democrats’ best-case scenario, if there are significant additional retirements, is that they pick up a total of nine open seats. This would leave them six short of a majority.

•Incumbents. Incumbent reelection rates for the past four election cycles have been over 96 percent. In an election that had no strong trend in favor of party, Republican incumbents would be slightly better positioned than Democrats. Republicans will defend 19 districts that Bush lost in 2004, and Democrats will defend 42 that Kerry lost. The large number of Democrats holding seats in Bush districts likely means that Republicans will defeat a few Democratic incumbents. To counteract this advantage, Democrats will have to do well against the 19 Republicans in Kerry districts. They will also have to beat some of the 24 Republican incumbents in districts that Bush won with 53 percent or less. They probably also have to gain a seat or two in the 26 Republican districts that Bush won with between 53 and 55 percent of the vote.

The lack of competitive seats makes taking over the House a large challenge for Democrats. To surf into the majority, Democrats will need a wave of considerable size.

Fortier is a research fellow at the American Enterprise Institute.