WASHINGTON  – Leading Republican presidential contender Mitt Romney took six of 10 states in Super Tuesday primaries, including a narrow victory in coveted Ohio.

Also in Ohio, Republicans selected a Jewish veteran to run for the U.S. Senate and longtime Rep. Dennis Kucinich, a consistent critic of Israel, lost in a Democratic primary.

In the biggest day of the primary season, Ohio was the biggest prize for Romney, who now owns a wide margin in the delegate total. The former Massachusetts governor won his home state and its neighbor, Vermont, as well as Alaska, Idaho and Virginia. With 99 percent of Ohio precincts reporting, Romney had 38 percent of the vote to 37 percent for Rick Santorum, the former Pennsylvania senator.

But Santorum picked up decisive victories in important southern states Oklahoma and Tennessee, and also won in North Dakota.

In Virginia, Romney faced only Rep. Ron Paul; Santorum and Newt Gingrich failed to place on the ballot. Head to head with Romney, the libertarian Paul scored one of his more impressive outcomes this primary season with his 40 percent total to 60 Romney's percent. Paul rejects foreign assistance, including for Israel.

Gingrich, the former speaker of the U.S. House of Representatives, won Georgia, the state he represented in Congress, keeping him in the race for now, although Santorum's decisive wins in Tennessee and Oklahoma seemed to dampen Gingrich's prospect of a rally.

The Wyoming caucus could last until the end of the week. The next primaries are in Alabama and Mississippi on March 13.  

Gingrich, Santorum and Romney each took time out of campaigning on Tuesday to address the American Israel Public Affairs Committee policy conference on its last day — Santorum in person at the convention centre in Washington, and Romney and Gingrich via satellite.

All three took shots at President Obama for not making more clear a military threat against Iran should it not stand down from its suspected nuclear weapons program.

AIPAC did not invite Paul, who opposes increased confrontation with Iran.