The Colorado secretary of state's office on Tuesday declared that organizers behind a recall petition against a Colorado lawmaker who supported gun control had enough valid signatures to set up the first potential recall of a state lawmaker in Colorado history.

The secretary of state said opponents of Senate President John Morse, D-Colorado Springs, gathered more than 10,000 valid signatures. They only needed 7,178 valid signatures, equaling 25 percent of all the votes cast in the previous state Senate election.

The recall election would likely in occur in September, though legal challenges could drag the process into October.

Lawyers for Morse are challenging the recall effort. They argued that the petition fails to use language defined in the Colorado constitution that "expressly include a demand for the election of a successor to the recalled official," The Denver Post reported.

"The constitution is clear, just as the courts are clear: no recall petition is valid without this specific language," Mark Grueskin, an election lawyer representing a Morse constituent who filed the legal challenge Tuesday told The Post.

The campaign to unseat Morse has become a national flashpoint in the gun control debate. Gun-rights activists from across the country have vowed to defeat Democrats who steered through laws that made Colorado the first state outside the East Coast to curb gun rights in the wake of mass shootings at an elementary school in Connecticut and a movie theater in suburban Denver.

The gun rights supporters were especially unhappy with new laws to expand required background checks for gun purchases and to limit the size of ammunition magazines. The laws take effect next month.

Jessica Kerns, spokeswoman for the group behind the recall, told the Colorado Springs Gazette her group plans to defend the petition against legal challenges from Morse supporters.

"We were expecting the most frivolous legal challenges to this and we're prepared to fight this," Kerns told the newspaper. "We're prepared to defend every single petition so that the peoples' voices can be heard."

Morse, a second-term incumbent who would be leaving office because of term limits after next session, has vowed to fight the recall. He didn't immediately return a call Tuesday after the recall petition was deemed sufficient.

Earlier this summer, Morse told reporters that the gun control measures were imperative after a bloody 2012.

"Keeping Coloradans safe from gun violence is very worth your political career," Morse said.

Morse's attorneys are asking that the validation of the signatures be reversed. A hearing will be scheduled for arguments at the Secretary of State's Office within two weeks. If there's an appeal there, it goes to Denver District Court.

A spokeswoman for the recall effort, Jennifer Kerns, called the Morse challenge part of the "normal crop of frivolous legal challenges."

"We are not surprised by their attempts to thwart this recall effort, and we will do everything we can to ensure that the voices of the people are heard," she wrote in an email.

If Morse resigns, the seat remains in Democratic hands because the party would appoint a senator to the vacancy. Democrats hold a five-seat advantage in the state Senate.

Democratic Sen. Angela Giron of Pueblo is awaiting word from the secretary of state about a similar petition filed against her. A decision in that recall effort was expected by the end of next week.

Recall efforts against two other Democratic lawmakers who supported the gun control measures fizzled. Democrats control both chambers of the state Legislature, as well as the governor's office.

The Associated Press contributed to this report.

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