PHOENIX -- A decades-old effort by Congress to make voter registration simple and uniform across the country has run up against a new era's anti-immigration politics. So on Tuesday when Arizona's primary polls open for governor, attorney general and a host of other state and local positions, as well as for Congress, some voters will be permitted to vote only in the race for Congress.

As voter registration drives intensify in the coming weeks, the list of voters on the "federal only" rolls for the November general elections could reach the thousands.

These are voters who could not produce the paper proof of citizenship that Arizona demands for voting in state elections.

The unusual division of voters into two tiers imposed by Arizona and Kansas, and being considered in Georgia, Alabama and elsewhere, is at the center of a constitutional showdown and, as Richard Hasen, an elections expert at the University of California, Irvine, put it, "part of a larger partisan struggle over the control of elections."

The issues will be argued Monday before a panel of the 10th U.S. Circuit Court of Appeals, in Denver.

This year, the circuit court temporarily blocked a lower court decision that would have forced federal officials to include the state's proof of citizenship requirements on registration forms used in Arizona and Kansas.

Apart from the legal principles at stake, groups working to sign up voters say the document requirements will most heavily affect minority groups, the poor, older adults and college students who move into the state, effectively disenfranchising some.

"These restrictive registration laws only add to the barriers facing Latino voters," said Raquel Teran, the Arizona state director of Mi Familia Vota, a national group promoting Hispanic political participation. Federal election officials and other experts say that illegal voting by noncitizens is rare and inconsequential.

The document requirements imposed by Arizona and Kansas are at odds with a 1993 federal law that requires potential voters in federal elections simply to swear on penalty of perjury, and, perhaps, deportation, that they are citizens.

Federal registration forms, accepted by nearly all the states alongside their own forms, do not ask for supporting paperwork like birth certificates, which some find hard to obtain.

In Kansas, while the federal-only rolls are small, about 19,000 applicants have been placed on a "suspense list" because their state forms are incomplete, in some cases because they did not provide the newly required proof of citizenship, said Dolores Furtado, president of the League of Women Voters of Kansas.

Registration drives in Arizona have been complicated by the need to offer different forms.

Most applicants fill out the state form if they have the required proof, which for many in Arizona is an Arizona driver's license first obtained since 1996, when citizenship status was registered on licenses.

Others use the federal form, ending up on the federal-only roll.

College students arriving from other states who want to vote in Arizona often are affected since they are unlikely to have birth certificates or other proof of citizenship with them, although they can change their status in the future if they obtain them.

On the eve of the fall semester at Arizona State University, numerous incoming students who registered to vote were astonished to learn that they had truncated rights.

"I'm going to be here for four years, perhaps longer, and I want to make my voice heard on local issues that will affect me," Sam Leffler, a freshman from Denver, said as he expressed frustration that he would be limited to voting in federal elections for now.

Republican officials like Horne and Kris Kobach, the Kansas secretary of state, insist that fraudulent registration is a significant threat, citing anecdotal reports and sporadic prosecutions.

But the federal Election Assistance Commission, when in January it again turned down the Arizona and Kansas requests to alter the federal form, concluded that the number of confirmed fraud cases is minute and "is not cause to conclude that additional proof of citizenship must be required."

Most elections scholars say that the simpler federal requirement of a sworn statement has worked well.

"If you're not a citizen, why would you jeopardize your status and even face deportation for something that is unlikely to make any difference?" said Michael McDonald, a political science professor at the University of Florida.

If the states win in court, the federal forms will be revised in those states, and two-tier voting will end -- with some potential voters unable to register.

If the federal elections agency and civic groups prevail, the federal form will remain as it is.

But the states have pledged, in that case, to maintain dual registries, even in the face of further court challenges.

"The federal government has no right to tell us what to do in our state elections," said Horne, the attorney general.

A Section on 08/24/2014