Another says Sanchez's opponent, state Rep. David Chavez, missed 146 legislative votes because he was absent from work.
Sanchez and Chavez are combatants in what may be New Mexico's most personal and most oversimplified campaign, the Senate race in Valencia County's District 29.
Republican Gov. Susana Martinez wants to displace Sanchez, a political enemy and the leader of majority Democrats in the Senate. A former district attorney, Martinez prosecuted the Baby Brianna case being used in the ads against Sanchez.
Martinez, who appears on camera, leaves viewers with the idea that Sanchez is soft on crime. He considers the ad an attack on the truth as much as it is on him.
"I support legislation that gives a life sentence to a person who intentionally abuses a child resulting in the child's death," said Sanchez, an attorney.
But in a 2005 vote, he did not favor the legislation referenced in the ad. Sanchez said he had good reason — namely the law's many tentacles could mean life sentences for people guilty of negligence but not actual child abuse.
He cited a Lovington case in which a domestic violence victim with post-traumatic stress disorder left her child in the same room with the abuser.
As for Chavez's work ethic, the ad targeting him also makes a generalization.
Legislators who are hard at work can and do miss floor votes. Members of legislative committees hearing significant bills may remain in session as the rest of the House or Senate assemble to vote on other legislation.
Another ad against Chavez refers to him as a puppet for Martinez.
Chavez, as a freshman representative, for a time opposed the governor's insistence that illegal immigrants be barred from driving in New Mexico. Now Chavez is trying to distance himself from his own legislation.
Of the licensing law, he wrote this on his campaign website: "I know this is a bad law that puts our public safety at risk. That is why I have always voted to repeal the law that gives illegal immigrants a driver's license."
His statement is true as far as it goes. But in 2011, Chavez sponsored a bill that would have given illegal immigrants privilege cards enabling them to drive in New Mexico but not other states.
Chavez said at the time that he was moved by those who fled the violence in Juarez, Mexico, where 3,100 people were murdered in 2010.
Providing driving privileges for illegal immigrants in New Mexico would be a humane act toward those trying to rebuild their lives in a safe place, Chavez told members of the House Consumer and Public Affairs Committee.
The committee blocked his bill on a 3-2 vote, so it never advanced to the full House of Representatives.
But the repeal bill moved ahead. Chavez then joined with all 33 Republican House members in voting to overturn the licensing law. The repeal later died in the Senate.
Sanchez has voted to continue the licensing law for illegal immigrants. In the last two years, he has been among Senate Democrats who pushed to add penalties for fraud to the law, saying that step should eliminate Martinez's objections.
Chavez, 54, an attorney, is the son of a former Democratic state senator and lieutenant governor, the late Tibo Chavez. Many say he is running against Sanchez at an opportune moment.
"I'm talking to people who say they voted for Michael in the past, but they won't this time," said state Rep. Alonzo Baldonado, R-Los Lunas. "I just have a feeling people want a change."
Los Lunas resident Guy Dicharry was not among them. He said he would cast his vote for Sanchez, 62, a senator for 20 years.
"He is always responsive," Dicharry said.
Jason Marks, a Democrat who serves on the state Public Regulation Commission, said he considered Sanchez one of the most dedicated and thoughtful legislators.
"Nobody pulls his strings," Marks said. "He's been an independent check on the lobbyists' ability to move bills that weren't a good idea."
Martinez, though, has accused Sanchez of obstructionism on important legislation.
She criticized him publicly in 2011 for not scheduling a final vote on a bill that would have retained about 2,500 third-graders statewide, all struggling to read.
Martinez campaigned on the measure, saying New Mexico is mindlessly promoting kids who are not able to keep up academically.
The retention bill made it onto the Senate calendar with 30 hours left in the session, but Sanchez did not schedule it for a vote. He said the bill was competing for time with dozens of other important measures and not all of them could be heard.
Angry Senate Republicans rebutted Sanchez's claim with a filibuster during the final hours of the session.
This race is Chavez's second against Sanchez. Chavez lost in 2000.
A win for Chavez this time would amount to a political coup for Martinez.
But if Sanchez is reelected, she could lose politically. Her chilly relationship with Sanchez could turn to ice, setting a stage where it would be harder than ever for her to advance her legislative agenda.