Rep. John Barrow, D-Ga., a perennially embattled Blue Dog who lost his seat in an expensive 2014 race. (Photo By Bill Clark/CQ Roll Call via AP Images)

Anne Kim is editor of Republic 3.0, a centrist policy site, and a senior fellow at the Progressive Policy Institute.

It’s tough to make it as a moderate in Congress these days.

Across the country, competitive purple districts have been gerrymandered into oblivion, replaced by seats that are safely red or blue. Activists at both extremes show no mercy toward elected officials who venture to advocate compromise. Even former House majority leader Eric Cantor — hardly moderate — fell victim to a 2014 primary challenge from a tea-party-backed opponent after his immigration stance ran afoul of the GOP’s far right wing. But perhaps most prohibitive: Being a moderate costs far more than being extreme. And the increasing expense means most moderates can’t compete.

Consider the case of Democratic members of the House, where long-standing, self-defined coalitions — New Democrats and Blue Dogs on the one hand and the Progressive Caucus on the other — separate moderates and liberals with reasonable clarity. (Members must apply to join, attend regular meetings and remain in good standing.) In the past three election cycles, self-described moderate lawmakers spent roughly twice as much as their liberal counterparts to win or defend their seats.

In 2014, for example, direct spending by members of the moderate New Democrat and Blue Dog coalitions averaged $2.01 million per campaign, according to an analysis of data derived from, the site of the Center for Responsive Politics. In contrast, members of the liberal Progressive Caucus each spent an average of $1.07 million on their races.

This disparity is even more extreme — greater than 3 to 1 — when all campaign spending is included. Counting spending by opponents and outside groups, the average campaign in a New Democrat or Blue Dog district cost $5.2 million in 2014, compared with an average of $1.57 million in Progressive Caucus districts.

And as ideological partisanship increases, this centrist premium is growing. For every dollar that the average Progressive Caucus member directly spent to defend his or her seat in 2014, the average moderate lawmaker spent $1.93. By comparison, moderates shelled out $1.54 for every campaign dollar spent by liberals by 2012 and $1.65 in 2010.

Similar calculations among Republicans are more difficult, because the distinctions between moderate and conservative coalitions are less well defined. While just three House members belong to both the New Democrats and the Progressive Caucus, 26 of the 63 House Republicans in the self-described centrist Main Street Partnership also belong to the conservative Republican Study Committee. (The Tea Party Caucus has been largely dormant since 2012.) But an anecdotal comparison between Main Street-only members and Study Committee-only members implies that the centrist premium applies to Republicans as well. For example, Main Street Rep. Fred Upton (Mich.) spent $3.9 million defending his seat in 2014 (not counting outside spending), compared with $1.4 million spent by Study Committee Rep. Marsha Blackburn (Tenn.). Likewise, sophomore Study Committee Rep. Markwayne Mullin (Okla.) directly spent $955,584 in 2014 (with zero spending reported by his opponent), while veteran Main Street Rep. Greg Walden (Ore.) spent nearly $3.5 million.

How to explain the high cost of moderate campaigns? Moderate districts are by definition competitive. And as the number of competitive districts shrinks, the ever-swelling sums of money flowing into politics are concentrated in fewer key contests. In 2014, outside groups spent an average of $2.2 million per race in New Democrat and Blue Dog districts, compared with an average of $299,339 in Progressive Caucus districts. All told, outside groups spent $121 million on moderate districts, vs. $20.4 million in liberal ones.

While lawmakers in moderate districts may be able to attract outside money, they’re also much more likely than those in liberal districts to draw well-funded opponents. In 2014, challengers of New Democrat and Blue Dog members spent an average of $947,901, while challengers of Progressive Caucus members spent an average of $202,555. In fact, in 21 of the 68 Progressive Caucus races included in this analysis, the putative challengers reported no spending at all.

And although campaign costs for longtime lawmakers tend to decline over time, “safe” veteran moderates still spend more than veteran liberals. In 2010, among moderate and liberal candidates who won by similar margins, moderates outspent their liberal counterparts by about $900,000 on average.

These figures show the disproportionate extent to which the burden of fundraising — and the burden of maintaining or winning the majority — falls to moderates.

The pressure to raise such enormous sums of cash with each campaign means too much time spent on fundraising and not enough time on policymaking. The high price of moderation may also deter well-qualified potential candidates from throwing their hats in the ring. And as targets of intense scrutiny by ideologically motivated outside groups, moderate lawmakers face immense pressure to abandon their centrist positions to avoid a primary challenge or to avert a flood of hostile outside spending.

No wonder, then, that the center in American politics is shrinking.

The solution isn’t to make races less expensive by making them less competitive. But changes that many have long called for — such as redistricting reform and campaign finance reform — are more urgently needed than ever.

As the centrist premium increases, so does the price of polarization.

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