It didn’t take long for Lt. Gov. Dan Patrick to try to kill the buzz around the first vote by Texas lawmakers in more than four decades to reduce criminal penalties for low-volume pot possession.

Patrick, a Republican who presides over the state Senate, pronounced House Bill 63 dead in his chamber early Tuesday, on the same morning that the House passed it on a final vote of 103-42 after giving it initial approval Monday.

Far from conceding defeat, however, advocates for the bill said they planned to rally supporters around the state and urge them to contact Patrick and various key state senators in a bid to turn the tide in their favor.

"Criminal Justice Chair @Whitmire_John is right that #HB 63 is dead in the @Texas Senate" Patrick tweeted on Tuesday. "I join with those House Republicans who oppose this step toward legalization of marijuana."

But state Sen. John Whitmire -- the Houston Democrat cited in Patrick's tweet -- said in an interview with the American-Statesman that he made the comments before the House voted to approve HB 63, which was revised prior to the vote in an effort to make it more palatable to some Republicans. Whitmire, who says he supports a reduction in penalties for low-volume pot possession, also said he didn't use the word "dead" to describe the bill's chances in the Senate.

"The reality is we don't have the votes in the Senate as we talk," Whitmire said. But he also said: "I don't believe it's dead and I'm going to do the best I can (to round up support). I'm trying to see if we have the votes in the Criminal Justice Committee to get it to the (Senate) floor."

Still, the lieutenant governor can block Senate action on a bill by preventing it from coming up for floor debate.

But the move would not be without political risk for Patrick in the case of HB 63 if it makes it that far. Nearly 70% of Texans support reduced penalties for small amounts of marijuana possession, according to a University of Texas/Texas Tribune poll last year, while the 2018 platform of the state’s Republican Party includes a plank calling for civil, instead of criminal, penalties for the infraction.

In addition, Patrick's stance seemingly puts him at odds with Republican Gov. Greg Abbott, who said during his re-election campaign last fall that he was open to reducing the charge for possession of 2 ounces or less to a Class C misdemeanor, so that low-volume marijuana offenders aren’t sent to jail. A spokesman for Abbott didn't immediately respond to a request for comment Tuesday.

House Bill 63 would make possession of an ounce or less of marijuana a Class C misdemeanor, punishable by a fine of up to $500 but no jail time. Currently, possession of 2 ounces or less in Texas is a Class B misdemeanor, with a maximum fine of $2,000 and up to 180 days in jail.

Texas last eased its marijuana penalties in 1973, when it re-classified low-volume possession from what had been a felony punishable by two years to life behind bars.

Pro-cannabis activist Heather Fazio said Tuesday that she still considers momentum to be on the side of HB 63's supporters, despite Patrick's tweet.

"We know that the vast majority of people around the state want to see these laws changed, so I'm not discouraged," said Fazio, director of Texans for Responsible Marijuana Policy, an advocacy group. "We are hoping that after receiving more input from Texans across the state and a better understanding of what this (bill) really does, the lieutenant governor will reconsider his opposition."

Earlier versions of HB 63 -- sponsored by state Rep. Joe Moody, D-El Paso -- would have eased the penalties even more for an ounce or less by decriminalizing the first few infractions, categorizing them as civil matters instead of misdemeanor crimes so that they wouldn't result in criminal records for offenders. But Moody added stiffer language to a substitute he introduced on the House floor Monday, in a bid to give the bill a better chance of clearing the Senate as well as the House and, ultimately, of winning Abbott's approval.

Patrick has previously voiced opposition to easing the state’s marijuana laws, as well as skepticism regarding a related push to increase Texans’ access to marijuana for medical purposes.