(CNN) - Democrats are raising the stakes in the gubernatorial battle deep in the heart of Texas.
The Democratic Governors Association launched a television commercial Tuesday attacking Republican Gov. Rick Perry, who's bidding for a third full term in office. The ad characterizes Perry as a career politician, with the narrator asserting that "on the issues, 25 years as a politician has changed Rick Perry – for the worse."
Despite the fact that Republicans have dominated statewide elections in Texas for over a decade and the political winds appear to favor the GOP this year, polls suggest that Perry holds only a single digit lead over former Houston Mayor Bill White, the Democratic nominee.
A survey released Sunday by Blum and Weprin Associates for a consortium of Texas newspapers indicates that Perry holds a 46 to 39 percent advantage over White among likely voters. Other recent surveys also put Perry's lead in single digits.
A Democratic source confirmed to CNN that the ad begins running in the Dallas television market Tuesday, where polls indicate Perry holds a substantial lead.
The DGA, according to the source, is spending up to $700,000 this week to air the commercial through "Lone Star First," an independent expenditure group in Texas that the DGA supports. Word of the ad was first reported nationally by the Washington Post.
In response to the commercial, the Perry campaign tied White to national Democrats.
"Considering they share the same policies, it's not surprising that President Obama's political machine would come into Texas to help Bill White's struggling campaign. Gov. Perry will continue talking about creating jobs, the economy, border security and other issues that truly matter to Texans," Perry campaign communications director Mark Miner told CNN.
Perry took over as Texas governor in late 2000, when then-Gov. George W. Bush stepped down after winning the White House. Perry is the longest serving governor in Lone Star state history.
The DGA is also launching ads this week against Massachusetts gubernatorial nominee Charlie Baker and Tom Foley, the GOP nominee in Connecticut.
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