Democratic state Treasurer Robert P. Casey Jr. (search), who hopes to challenge Republican Sen. Rick Santorum (search) next year, increased his lead to 14 points in a poll released Wednesday.

Casey, the son of a former governor, was favored in the Quinnipiac University poll (search), taken amid Santorum's high-profile push of President Bush's Social Security overhaul plan and his backing of the recent congressional intervention in the Terri Schiavo case.

Casey was favored by 49 percent of respondents in the telephone poll, conducted April 13 to Monday. Thirty-five percent supported Santorum, while 13 percent were undecided.

A poll in February showed Casey was favored by 46 percent of respondents to 41 percent for Santorum.

"Santorum has become a more controversial public figure in the past two months and Bob Casey, without doing much of anything to attract headlines, is the beneficiary," said Clay F. Richards, assistant director of the Connecticut university's polling institute.

The 1,395 respondents in the latest poll were asked how Santorum's role in the Social Security battle and the Schiavo case affected their view of him. In each case, one-third or more said it made them less likely to vote for him. About 15 percent said it made them more likely to support Santorum.

The statewide poll has a sampling error of plus or minus 2.5 percentage points.

Santorum, elected to the Senate in 1994, is chairman of the Senate Republican Conference (search), the party's third-ranked leadership position in the Senate.