Pro-choice Republicans are much more likely to lose primaries than pro-life Democrats. Further, Democrats are more likely to lose general elections for being pro-choice than Republicans for being pro-life, because there are significantly more voters who will oppose any pro-choice candidate than there are voters who will oppose any pro-life candidate.

Democrats who voted for the Affordable Care Act fared worse than Democrats who voted against it. By contrast, outside of Blanche Lincoln, no members of Congress were seriously threatened with losing an election because they opposed the public option.

Even though ending the Bush tax cuts on the wealthy is popular, candidates are still better off electorally if they favor extending them, given the monetary forces that will line up to support those who advocate extending them and to thwart those who oppose.

Democrats who failed to support comprehensive immigration reform have never been replaced by candidates who are more progressive on that issue. By contrast, right-wing demagoguery on immigration has been at least moderately successful in both primary and general elections since 2006.

No member of Congress has ever lost an election for not doing enough to combat climate change. However, Rep. Bob Inglis was crushingly defeated in a Republican primary last year at least partially because of his real support for action on climate change.

The sad truth is that it is reasonable for candidates and elected officials to believe they have more to fear for supporting progressive causes than for supporting conservative ones. Even when polls show progressive causes to be popular, the forces opposing those causes still make a disproportionate impact on electoral outcomes.

Not everyone reading this, and maybe not even most people reading this, will agree with the idea that there are few electoral repercussions for elected officials who do not support progressive legislative causes. Probably the most common counter-argument is that the Democratic base becomes depressed when Democrats oppose progressive causes, resulting in less activism for Democratic candidates and lower turnout among Democratic voting groups. Thus, the argument concludes, opposing progressive causes actually does carry a serious risk of electoral defeat.

However, there are two problems with this argument:

First, it's not supported by any evidence. Self-identified liberals formed identical shares of the electorate in the last two midterm elections, the only real apples-to-apples comparison available. In both 2006 and 2010, liberals composed 20% of the electorate. Further, they were actually slightly more pro-Democratic in 2010 (90%) than 2006 (87%).

Second, the argument itself is a tacit admission of progressive weakness. Saying that progressives will just stay home acknowledges that progressives cannot defeat bad Democrats with better candidates. Instead, the only option for progressives in the face of betrayal or legislative defeat is to just withdraw from politics itself. Since that state of affairs will actually increase right-wing power, one has to wonder why those who oppose progressive causes would be worried about it happening. Progressives staying home poses no threat to those who oppose progressives.

A more credible counter to the belief that pushing progressive policy damages candidates is that most swing voters don't make decisions based on the perceived ideological orientation of the legislation that candidates have supported. Instead, when times are getting worse, the governing party gets booted from swing districts. When times are getting better, the governing party wins swing states and districts. So, if progressive policy can result in more voters feeling their lives were improving, then Democrats who oppose that policy do real electoral damage to themselves.

Now, I actually accept that rebuttal, so I'm not going to spend time arguing against it. But it is a very abstract and academic argument that will not be persuasive to candidates and operatives whose lives are filled with the concrete experience of standing for office. Political science papers disputing causality in electoral outcomes are not going to overcome generations of institutional belief that appealing to the left will cause you to lose elections. So if we are going to convince decision-makers that there are serious political repercussions to opposing progressive causes, then we are going to have to do something much more than engage in abstract argumentation.

We have to start winning elections in ways so that the majority of political observers believe the defeated candidate lost because s/he opposed one or more progressive legislative priorities. Just defeating someone who opposes progressive legislation with someone who supports it is not enough. A wide array of pundits, candidates and political professionals must believe that opposition to progressive policies was the primary reason an elected official was removed from office. That is the only way we are going to start convincing people that opposing progressive legislation is truly bad idea for someone's political career. As such, it's also the only way we're going to start getting progressive legislation passed on a regular basis.

If political observers think we won an election because our opponent had corruption issues, it won't build progressive power. If political observers think we won because the other side had crazy candidates, it won't change legislative outcomes. If people think we won because we were well-organized or because we used clever new tactics, then they will come to our seminars about how to run a campaign–but they will not pass our desired public policy into law. Hell, even if we win because the country is in the dumps and we get a wave election, that will give us a brief shot at power but nothing over the long-term (see 1977-1980, 1993-1994, and 2009-2010).

From this perspective, the best fight the netroots ever picked, at least before 2011, was the Lamont vs. Lieberman primary in Connecticut in 2006. Every political observer in the country knew—and admitted!—that fight was about Lieberman opposing withdrawal in Iraq. As such, when we won the primary, a meaningful blow was struck against the idea, widespread in professional political circles, that pissing off liberals has no meaningful electoral consequences. It delivered the netroots the credibility that had escaped us when candidates who opposed the war in Iraq failed in the 2004 presidential primaries.

Sadly, losing the 2006 Connecticut general election to Lieberman might have set back our efforts on this front even further than winning the primary advanced it. Even so, Lamont vs. Lieberman is exactly the type of fight progressives need to be picking, and pouring a disproportionate amount of our resources into, in order to build real legislative power. Right now, there are at least two fights that fit this mold:

The first is the recall campaign in Wisconsin. The vast majority of political observers know and admit that this campaign is about Republicans stripping collective bargaining rights. As such, winning the recalls has real potential to strike a blow against the idea that pissing off the left has no electoral consequences. We can show that stripping collective bargaining rights can and will result in the people supporting it being removed from office. This will have a major impact on other states.

The second campaign that currently fits this model is the battle over Medicare. This is because it isn't really that hard to get candidates, pundits and political professionals to believe campaigns can be lost for favoring cuts to Medicare and/or Social Security. After all, the reason why politicians are labeled "courageous" for proposing cuts to Medicare and Social Security is because entitlement programs are one of the very few areas where politicos never stopped doubting that opposing the poor and middle class would result in severe electoral consequences. Further, the NY-26 special election, even though it featured a semi-major third party candidate, was an important step in cementing that belief. Imagine how deeply ingrained that belief will become if we retake in the House in 2012 while defeating Paul Ryan!

If tactics are how you fight a battle, but strategy is the rationale behind what battles you choose to fight, then the strategy to building lasting progressive power is to choose to fight battles like Lamont vs. Lieberman, the Wisconsin recall elections, and going explicitly after Republicans—or anyone—on Medicare and Social Security. We can't just win elections, and we can't just win elections with Better Democrats. We have to win elections in which people believe the outcome was determined by popular support for progressive policies, and a backlash against those who opposed them. That's the only way politicians will believe they have to support progressive policies in order to stay in office, and thus the only way progressives are going to stop being thwarted and disappointed even when Democrats are the party in power.