By David M. Shribman
Executive Editor of the Pittsburgh Post-Gazette

Last week's presidential primaries from New Jersey to California seemed to settle the big questions in this phase of the race to the White House. Though he continued to antagonize members of his party, Donald Trump maintained his march through the states. Though she still has not captured the heart of her party, Hillary Clinton claimed the Democratic nomination. 

But though the primary season has ended -- Tuesday's contest in the District of Columbia is but a meaningless coda -- a feeling of unease still pervades American politics. The nomination fights are finished, but there is no sense of closure. 

That's because vital questions -- questions that get to the heart of America's self-identity and the identity of the two apparent nominees -- still nag. Here are three of the principal ones: 

-- Is American politics corrupt or rigged? 

This is perhaps the most searing question that Trump, an accomplished manipulator of rigged situations, has posed during a campaign that left the Republican establishment in tatters even as it shattered every assumption, every convention and every code of civil comportment that has governed American politics for more than a century. 

He may have raised that question in a surly, self-indulgent and self-serving manner, and his rhetoric may have been more comic than considered, but make no mistake: Trump has posed the ultimate question in the politics of a country whose founding mythology is that the people should rule in a governmental structure open to all voices. 

But the sobering message to the institution that regards itself as the representative of the people, the Democratic Party, is that its nominating process may be more rigged than is its rival's. 

The considerable influence that the more than 700 superdelegates had in pushing Clinton over the top underlines the role that established figures play in the Democrats' nominating process. 

Democrats have revolted against this in the past; in 1969 the party's Commission on Party Structure and Delegate Selection banned the selection of ex-officio delegates, such as House members and lieutenant governors, to the party conventions. This defanged the party establishment so brutally that after the next convention, in 1972, there was a counter-revolution. 

That year, nearly all the top party members sided with Sen. Edmund S. Muskie of Maine, whose campaign ended April 28, only days before the Ohio primary, where Muskie's delegate slate won less than 9 percent of the vote. The result: Many party leaders were shut out of the convention that eventually nominated Sen. George McGovern of South Dakota. 

All that produced another commission, which created the superdelegates who have been so important in recent contests. "Superdelegates rush as fast as they can to get behind a candidate they think will win," said Ken Bode, the research director of the 1969 commission. "They bend the convention away from democratic rule. There are fewer options for voters to affect the outcome because superdelegates always want to go with who looks to be the winner." 

For months, Sen. Bernie Sanders of Vermont left the superdelegate question on the table -- a case, it now seems, of unilateral political disarmament in a volatile campaign. It was Trump who raised the question and who taunted Sanders to engage it. (Who says that there are no philosophical bridges between the Sanders and Trump campaigns, which may be a serious threat to Clinton as she goes forward?) 

A titanic struggle now looms. It may break into the open at the Democratic convention in Philadelphia, where the supporters of Sanders may mount an attack against superdelegates at a conclave controlled by the very superdelegates who helped boost Clinton to victory. 

-- Which profiles will the two apparent nominees put forth? 

No election in modern history has included two candidates who so desperately need to adjust their personae. The fight for the White House now has come down to two candidates who are works in progress: 

One is a former campus rebel at Wellesley College who became a member of the establishment at the Rose Law Firm and in the governor's mansion in Little Rock en route to the White House, the Senate and the State Department, and whose political success may now require that she appeal to the rebels who rejected her candidacy even as she shifted left. 

The other is a rich man's son educated in an exclusive Ivy League business school who became an outlaw tycoon with decorating tastes bordering on the vulgar, and who ran as an outsider but whose political success may now require that he behave with the very restraint he mocked viciously en route to his nomination. 

Political professionals are telling these combatants to make dramatic alterations in their political profiles. That could aid their prospects, but the very process of doing so may only underscore how empty, corrupt and opportunistic is modern American politics. 

-- Who votes? 

This is always the ultimate question in American presidential elections and is no less vital this time, when the question may not be which campaign can mobilize its supporters but instead which campaign suffers the greater loss of its core constituents. 

It can never be good when small numbers of people participate in an election, but this is the unusual juncture when non-participation may be a deciding factor. (Outsider politicians often talk about bringing new voters into the process -- the Rev. Pat Robertson made this boast in 1988, Trump and Sanders did so this year -- but there is little clear evidence these claims make substantial differences. Instead, natural changes in the electorate, such as the maturing of one generation or the eclipse of another through mortality, or transformations of the nation's demographics through immigration, usually are more important.) 

This year there are alarming signs that vast swaths of the American electorate either are alienated -- and alienation was the oxygen of the Trump and Sanders campaigns -- or find the apparent nominees odious. The negative ratings of these two candidates shatter all previous records. 

So here is the figure that shows the depths of the despair and that demonstrates how important are the three questions emerging from this campaign: The latest Rasmussen Reports national telephone survey of likely voters shows that nearly a quarter of them aren't likely voters at all: a pox on both your houses, substantial numbers of Americans are saying, and on the two parties and the political system as a whole. 

(David M. Shribman is executive editor of the Post-Gazette (dshribman@post-gazette.com, 412 263-1890). Follow him on Twitter at ShribmanPG.)

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