Although the single-line method may be faster, Mr. Hammack says customers generally prefer to "jockey for position" in separate lines.

WSJ: Find the Best Checkout Line

House leaders have said in the press caucus that they are ready to -- if the Supreme Court rules it unconstitutional -- they would push for a single-payer method.

WHITEHOUSE: Press Briefing

Councillors in Scotland are usually elected to multi-member wards under proportional representation using the "single transferable vote" method.

BBC: Labour wins South Lanarkshire Council majority