Santorum says GOP contest only at halftime

MARS, Pa. — Republican Rick Santorum said Tuesday night his presidential campaign would continue despite triple losses to rival Mitt Romney in primaries in Wisconsin, Maryland and the District of Columbia.

"There are no marching bands. We're hitting the field. The clock starts tonight," Santorum told a sparsely attended election night party outside Pittsburgh. He had three campaign events scheduled across Pennsylvania on Wednesday.

Santorum said the GOP contest had only reached halftime, with half of the 1,144 delegates needed for the nomination having been selected. However, The Associated Press count of delegates showed Romney leading the race for delegates with at least 646 delegates. Santorum had just 272.

Santorum predicted victory in Pennsylvania's primary on April 24. He represented the state in the House and Senate for 16 years but lost his 2006 Senate race in a landslide.

Santorum's defiance did little to mask his poor showing Tuesday, particularly in Wisconsin, where he campaigned heavily for several days and where an allied independent group spent nearly $900,000 on television ads. Santorum's effort to target Midwestern industrial states like Wisconsin has consistently fallen short despite his effort to paint Romney as a plutocrat out of touch with the concerns of workers.

Exit polls taken for the AP and the television networks found Romney winning blue-collar and very conservative voters in Wisconsin.

Santorum did not back down on his criticism of Romney, saying the former Massachusetts governor's push for a health care mandate in his state made him unsuitable to carry the party's banner against President Barack Obama in the general election.

Santorum said Republicans need to nominate a candidate with "convictions forged in steel, and not on an Etch A Sketch" — a reference to a comment from a Romney aide suggesting the campaign would shake up its strategy like an Etch a Sketch in the general election.

Follow Beth Fouhy on Twitter at www.twitter.com/bfouhy