A recent poll surveying attitudes toward the current political acrimony revealed an interesting and meaningful contrast between Republicans' and Democrats' views that explains a lot about recent primary election results.
The poll, which independent pollster John Zogby conducted for Allegheny College's Center for Public Participation, showed that Republicans believe it's more important for politicians to stand firm in support of principles, while Democrats favor compromise to get things done.
Those tendencies were even stronger among the parties' more ideological members. Those calling themselves very conservative favored standing firm on principle by better than 4-to-1; self-styled liberals backed compromise by 5-to-3.
That helps explain why Republicans in recent high-profile primaries, starting in March in Texas, supported more outspokenly conservative candidates. Democrats, meanwhile, seemed to cast more pragmatic votes that often defied easy ideological classification.
Those rival tendencies were evident again Tuesday.
Conservative insurgent Rand Paul's victory in the Kentucky GOP senatorial primary followed the pattern set by Gov. Rick Perry's primary victory in Texas, Sen. Bob Bennett's convention loss in Utah and Marco Rubio's rise in Florida.
Paul's win underscored Republicans' desire to pick candidates more likely to stand firm for principles than to compromise on issues such as spending.
Conservative challengers haven't won every race; establishment Senate candidate Dan Coats survived a tea party challenge in Indiana. But most key primaries have shown conservatives' clout in the Republican Party.
Tuesday's headline Democratic contests were less ideological.
In Pennsylvania, Rep. Joe Sestak unseated veteran Republican-turned-Democratic Sen. Arlen Specter. Though President Barack Obama endorsed Specter when wooing him to switch parties, he avoided him in recent weeks; the outcome had little to do with Obama's standing.
Rather, Pennsylvania Democrats rejected a Johnny-come-lately Democrat who epitomized old-style Washington politics and thus probably would have been the easier general-election foe for Republican Pat Toomey in November.
Similarly, in Kentucky, Democrats seem to have picked the fresher candidate, Attorney General Jack Conway. And in Arkansas, while labor unions and outside liberal groups funded Lt. Gov. Bill Halter's challenge to Sen. Blanche Lincoln, the pattern of their near-draw suggests the vote was less ideological than pragmatic.
Lincoln's lackluster showing means Halter probably will be favored in their June 8 runoff, and his rise suggests a newer face may be more electable in the current anti-incumbent climate. In any case, either would be an underdog against Republican Rep. John Boozman.
Earlier this month, liberal critics failed to unseat two North Carolina conservatives who opposed Obama's health reform bill, while an Ohio conservative lost to a supporter of the measure.
There may yet be instances in which liberal critics damage the re-election prospects of conservative Democrats who opposed health reform. But the one who seems most vulnerable, Rep. Michael Arcuri in upstate New York, hurt himself by first supporting the measure, then opposing it.
In West Virginia, a more conservative challenger unseated veteran Rep. Alan Mollohan, but that outcome may have turned more on Mollohan's ethical issues than ideology.
In any case, these Democratic primaries lack the clear ideological pattern of many GOP contests. Races are mainly being settled by local political currents, candidate caliber and, to some extent, the general anti-incumbent mood.
Interestingly, in a race that may have greater significance for what might happen this fall, Republicans failed Tuesday to capture the rural, conservative Pennsylvania seat held for 35 years by the late Democrat John Murtha.
Democrats were thrilled, even though the victor, longtime Murtha aide Mark Critz, ran as a critic of Obama's health plan, abortion rights and limits on firearms.
It's another sign that the Democratic Party is likely to remain an occasionally unwieldy ideological coalition, albeit liberal-led, contrasted with the increasingly monolithically conservative GOP.
And that augurs poorly for any future cooperation.
Leubsdorf is the former Washington bureau chief of the Dallas Morning News.
THE DALLAS MORNING NEWS