We’re finally seeing a response to all that money pouring in on the conservative side into SuperPACs and electoral-focused independent expenditure groups. George Soros and other finders have opened their pocketbooks, but they will orient their spending a bit differently:

After months on the sidelines, major liberal donors including the financier George Soros are preparing to inject up to $100 million into independent groups to aid Democrats’ chances this fall. But instead of going head to head with the conservative “super PACs” and outside groups that have flooded the presidential and Congressional campaigns with negative advertising, the donors are focusing on grass-roots organizing, voter registration and Democratic turnout.

The departure from the conservatives’ approach, which helped Republicans wrest control of the House in 2010, partly reflects liberal donors’ objections to the Supreme Court’s Citizens United decision, which paved the way for super PACs and unbridled campaign spending.

But in interviews, donors and strategists involved in the effort said they also did not believe they could match advertising spending by leading conservative groups like American Crossroads and Americans for Prosperity, and instead wanted to exploit what they see as the Democrats’ advantage in grass-roots organizing.

“Super PACs are critically important,” said Rob Stein, the founder of the Democracy Alliance, a group of liberal donors who will convene near Miami this week to discuss where to steer their money this year. But the liberal groups, he said, believe that local efforts and outreach through social media “can have an enormous impact in battleground states in 2012.”

This isn’t all that much of a departure. Soros’ main expenditure in 2004 was the Americans Coming Together project, which basically did all the field operations on the Democratic side during the Bush-Kerry campaign. The problem, of course, was that the project vanished almost immediately after 2004, and no advantage was gained from it over time. That’s what this looks like to me. The first round of money will go to America Votes, which is mostly a field operation, and to American Bridge, an oppo shop. I would hardly call this “grassroots” organizing, certainly not at the level of ideas. It may be an improvement on flushing money down the drain with political ads of a disproportionate nature, but it’s nothing long-lasting that would compete on an ideological level.

The important point here is that the pot of money is simply bigger for conservative causes and ideas. It arguably always has been. But that’s certainly true now. Conservative donors spend far more on messaging and think tanks and ideological work in addition to the mass of money on political advertising. Liberals seem to have an advantage on ground-level work. But without a marketplace of ideas, that can be a bankrupt enterprise, or at least a wholly oppositional one. Exactly what  is the liberal set of ideas and policies that any candidate for office can tap into with ready-made research, data and information? What are the simple bullet points that the message machine can provide?

In favor of an ground-level organizing effort – which is already replicated inside the Obama campaign – that has been sacrificed. Meanwhile, conservatives swamped liberals with money, particularly in state- and district-level races, in 2010, the first post-Citizens United election. It may be a good bet to go with ground-level funding. But there’s still a yawning gap in the ideas marketplace.