Political scientists use a number of different models to understand voter behavior. Two such models are the “prospective voter” and the “retrospective voter.” Prospective voters look at what candidates are promising to do in the future. Retrospective voters are the “What have you done for me lately?” voters — i.e., did the incumbent pass laws that the voter likes.

Obviously, most voters are a mix of those two models. As a result, incumbent politicians, especially those of the majority party, need to develop strategies that appeal to both prospective and retrospective voters. I imagine that most political scientists using these models to analyze the Republicans this year would come to the conclusion, “The GOP sucks!”

First, ask yourself, what are House and Senate Republicans promising going forward? If you have to think real hard, it’s because the GOP isn’t really offering much. By and large, GOP candidates aren’t telling us what they will do in 2007-2008 should Republicans retain control of Congress. There is no common agenda of, say, tax cuts, spending reductions, entitlement and immigration reform, etc. Rather, their message amounts to what one could call a “negative agenda.” In other words, “Don’t vote for the Democrats because they will be worse than we are.” Not exactly an inspiring message.

While the GOP is lousy on the prospective side, it is arguably worse on the retrospective side. Congressional Republicans don’t have many accomplishments to run on. Let’s run down the list of failures and missed opportunities:

Iraq War: President Bush should have appointed the Baker Commission shortly after he won reelection. Further, Congressional Republicans should have pushed Bush to do this. Such a commission would have given Bush and Republicans some cover for taking a new direction in Iraq — possibly adding new troops or setting a time table for Iraqi troops to take over the security function in Iraq. This would have made the Iraq War far less of a liability for the GOP and kept the base from feeling worn out on the issue.

Social Security Reform: While President Bush pushed for this in early 2005, the reception it received from Capitol Hill was less than enthusiastic. In fairness, Bush never put forward a concrete plan that Republicans could rally around. But Congressional GOP inaction ensured that reform never even got off the ground.

Extending Tax Cuts: No progress at all on this. Aside from a brief attempt at making the death-tax repeal permanent, the GOP has done little to promote tax relief. It has also failed to connect the Bush tax cuts to the good economy. One can only hope that the GOP has some grand strategy to hit the Democrats over the head with these tax cuts as their 2010 expiration date draws near.

Gay Marriage: Early in 2005, President Bush told the Washington Post that he would not lobby Congress hard for the Federal Marriage Amendment since there wouldn’t be enough votes to win unless the courts overturned the Defense of Marriage Act. This must have been a big let down for social conservatives, as it seemed that Bush only cared about the gay marriage issue as long as it helped to win elections. Since then, Congress has largely dropped the matter. Thus, expect a lot of conservative Christians to stay home tomorrow evening.

Spending Reductions: Other than a few spending offsets in the wake of Hurricane Katrina, this has continued to be the Congress of Drunken Sailors. Pork addicts like Ted Stevens, Don Young and Jerry Lewis set the tone on spending for the GOP in Congress. To fully understand this, it would be like letting Gloria Steinem, Catharine MacKinnon, and Kim Gandy set abortion policy for the Vatican.

EVEN WHERE THE GOP HAS GENUINE accomplishments, they have been achieved in such a way as to sour the base. These include:

Immigration Reform: Yes, Congress passed and President Bush signed a bill that boosts border security. But that was only after House Republicans refused to play along with the amnesty being pushed by the President and Republican Senators. By refusing to make security the top priority, Bush and Senate Republicans may have caused the conservative base to stop trusting GOP politicians on immigration. Sad to say, it is the House Republicans who may suffer the worst for this.

Judicial Appointments: Sure, President Bush won the confirmations of John Roberts and Sam Alito, accomplishments to be proud of. Yet this was sullied with the Harriet Miers fiasco, when President Bush showed that he was willing to let cronyism trump sound judicial policy. For their trouble, conservatives who opposed the Miers’ nomination were panned as “sexist” by the administration. Then, of course, there is the recurring fecklessness of the Senate Republicans in getting conservative jurists appointed to the lower courts. The base seems dispirited on this issue, and who can blame it?

The old adage applies to this election: you can’t beat something with nothing. That, however, is exactly what House and Senate Republicans are trying to do. They have no serious achievements to promote, and no agenda for the future. All they have to offer is, “It will be worse with the Democrats in control.” Looking over some old news articles, that was also the GOPs’ problem in 1986. We all know how that turned out.

David Hogberg is a writer living in the Washington area. He also hosts his own website, Hog Haven.