Rove The 2010 midterm elections will be bad for Democrats.

But the question is, will their losses be worse than the post-World War II average of 24 House and four Senate seats lost by the party that holds the White House?

The answer isn’t locked in yet — and will depend on the conf luence of many elements. Here are several that matter.

The most imp ortant metric is presidential job approval. Obama is now at 51 percent in Gallup and 47 percent in Rasmussen. When Democrats lost 54 seats in 1994, Bill Clinton’s job approval was at 46 percent.

Every president has been lower by the midterm than at the start of that year. Obama was at 50 percent in early January. Add a persistently high jobless rate and it points to a worse-thannormal year for Congressional Democrats.

A second factor is the generic ballot, which measures voters’ preference for voting for a Republican or a Democrat. At the end of the 2008 election, Democrats led in the Gallup generic ballot by 12 points. Today, the parties are tied at 45 percent. At this point in 1994, the GOP was nearly five points behind. By Election Day, it was five points ahead.

The GOP also enjoys a lead in the polls that now sample likely voters. In Rasmussen, the GOP is ahead 44 percent to 37 percent.

Intensity matters as well. The latest Fox/Opinion Dynamics poll reports two-thirds of Republicans are “extremely” or “very” interested in the midterms, compared to only half of Democrats. Older voters are almost twice as likely as younger voters to be interested. And seniors now favor the GOP 50 percent to 41 percent.

Look for the Obama White House to try raising Democratic intensity in the months ahead, especially among blacks, Latinos and liberals. The president’s harsh attacks on the Arizona immigration law are part of this strategy.

Another important metric for the Fall is the turnout for primaries. Is it rising or falling compared to four years ago? The results so far are bad for Democrats. For example, in Ohio, Democratic participation was down 24 percent over the last midterm while GOP turnout was up 64 percent.

Registration in states that enroll by party have shown major-party and independent registration down from 2008 while third-party registrations — admittedly a small part of the total electorate — are up modestly, according to George Mason University Professor Michael McDonald.

Congressional job approval is an anemic 28 percent in a recent Associated Press poll. Thirtytwo percent of Americans told ABC/Washington Post pollsters in late April they’d vote to re-elect their congressman, while 57 percent said they’d look for someone else — the highest number since 58 percent responded that way to an ABC/Washington Post poll in October 1994.

Karl Rove is former senior advisor to President George W. Bush.