Hartford - A new statewide poll released Thursday shows support for Connecticut's death penalty is growing among voters, despite efforts by some legislators to abolish capital punishment.

Sixty-seven percent of registered voters favor the death penalty, a new high for the state, according to Quinnipiac University Poll Director Douglas Schwartz. An earlier Quinnipiac survey in October found 65 percent supported the death penalty.

The 2007 home invasion in Cheshire, where a mother and her two daughters were killed, appears to have generated support for the death penalty. A 2005 poll showed 59 percent supported capital punishment, Schwartz said.

"Historically, voters favor the death penalty about two-to-one when they are asked a simple yes-no question. When they are offered the choice, however, between the death penalty and life in prison with no chance of parole, voters have been evenly divided," Schwartz said. "In Connecticut, the Cheshire home invasion murders appear to have changed that. Now voters back the death penalty no matter how we ask the question."

The General Assembly's Judiciary Committee this week held a public hearing on legislation that would abolish the death penalty for crimes committed when or after the repeal takes effect. A similar bill passed in 2009 but then-Gov. M. Jodi Rell vetoed it. Gov. Dannel P. Malloy reiterated this week that he would sign such legislation into law.

Both the chief state's attorney and the chief public defender warned state lawmakers that making the repeal prospective will not guarantee that the 10 men on death row will still be executed. They said challenges could be brought questioning the legality of creating two classes of people, one subject to the death penalty and the other not.

Thursday's poll shows that 74 percent of voters support the death penalty for Steven Hayes, one of the two suspects in the Cheshire case who was convicted and sentenced to death last year. Seventy-two percent of voters support the death penalty for Hayes' co-defendant, Joshua Komisarjevsky, who still faces trial and has not been found guilty.

The same poll shows 79 percent of voters support allowing a doctor to prescribe marijuana for medical purposes. Sixty-five percent support decriminalizing possession of small amounts of marijuana, a proposal made by Malloy.

Voters also back proposed legislation that would allow liquor stores to open on Sundays by a 66 percent to 31 percent margin. Schwartz said that marks the highest level of support for the question. Last March, 56 percent supported Sunday sales while 39 percent opposed it. Malloy has said he supports Sunday liquor sales.

Fifty percent of voters oppose allowing grocery stores to sell wine or hard liquor, while 43 percent support the idea.

The telephone survey of 1,693 voters, conducted March 1 through 7, has a margin of sampling error of 2.4 percentage points.