Originally Published: 29 SEP 21 07:46 ET

Updated: 29 SEP 21 11:03 ET

By Veronica Stracqualursi and Terence Burlij, CNN

(CNN) -- Matthew Dowd, a former strategist for George W. Bush's presidential reelection campaign, announced Wednesday he would launch a campaign as a Democrat against Texas Lt. Gov. Dan Patrick in next year's midterm election.

Although Dowd hasn't identified as a Republican in years, his candidacy is the latest proxy fight in the larger nationwide battle over Republicans who have attached themselves to former President Donald Trump and his brand of politics versus moderate, establishment figures such as Dowd.

In a two-and-a-half minute announcement video, Dowd, who publicly split with Bush and the GOP in 2007, criticized Republican politicians in Texas, singling out Patrick as "cruel and craven."

In particular, Dowd criticized Patrick's handling of the Covid-19 pandemic in Texas, saying the No. 2 official in the state "didn't respond to it based on science and prevented local officials from doing the things they needed to do to keep their community safe."

He slammed Patrick for pushing a bill that allows Texans to openly carry a gun in public without a permit, criticized his response to the Texas power grid failure earlier this year, and accused him of attacking voting rights and waging "a culture war, decimating Roe v. Wade and attacking the diversity of our state."

"We need more officials to tell the truth, who believe in public service and common sense with common decency for the common good and the idea of servant leadership," Dowd says in his video, adding, "Dan Patrick believes in none of those, and that is why I'm running for the powerful office of lieutenant governor."

Dowd, however, faces tough odds to become the next lieutenant governor in a traditionally red state in which Republicans control the governor's mansion and both chambers of the legislature, though shifting demographics in suburbs have given Democrats hope in statewide elections in recent years.

First elected to the seat in 2014, Patrick won a second term in 2018 by more than 51% of the vote, beating Democratic challenger Mike Collier by less than five percentage points.

Collier, an accountant and former senior adviser to Joe Biden's campaign in Texas, is considering a rematch against Patrick by launching an exploratory committee for lieutenant governor.

In response to Dowd's announcement, Collier's campaign knocked Dowd's previous affiliation with the Republican Party and prior work promoting Bush's policies.

"After 20 years working to elect Republicans across the country, we welcome Matthew Dowd back to the Democratic Party. Mr. Dowd—you may notice things have changed a lot since you were working for Republicans," Collier's deputy campaign manager, Ali S. Zaidi, said in a statement Wednesday. "Democratic voters will be interested to hear how selling a false war, ensuring the deciding Supreme Court vote to overturn Roe v. Wade, and leading the charge to pass numerous anti-marriage equality ballot measures have shaped your current views."

Dowd made his national name in politics as Bush's chief campaign strategist for the Republican incumbent's 2004 campaign.

A lifelong Democrat, he left the party in 1999 over his disillusionment with Bill Clinton and switched to the GOP, seeing Bush as a someone who could bridge divides, according to The New York Times. But Dowd broke with Bush and the Republican Party in 2007 over the Iraq War, the Times reported, and identified as an independent.

He also previously worked for Texas Lt. Gov. Bob Bullock, who was the last Democrat to win the office of lieutenant governor in the Lone Star State and served throughout the 90s.

Dowd, a former political analyst for ABC News who stepped away from the role in January, has often criticized Trump and the GOP's politics, while Patrick, who is seeking his third term in office, was endorsed by Trump in May.

Trump carried Texas in 2020 by more than 52% of the vote.

This story has been updated with additional background information.