HARRISBURG — Pittsburgh’s suburbs, perhaps the most politically poked and prodded territory in Pennsylvania recently, are under the microscope again in a state legislative election that some see as an early test of President Donald Trump’s strength in a critical battleground ahead of 2020.

The open state Senate seat is in a territory historically influenced by Republican enclaves outside the Steel City but also viewed as increasingly friendly to Democrats, even as the area’s more rural coal regions have swung to Republicans.

Tuesday’s special election pits Republican D. Raja against Democrat Pam Iovino for a seat largely controlled by Republicans the past 50 years.

Raja is the chairman and chief executive of an information technology consulting firm he helped start after he emigrated from India. Iovino is a Navy veteran who served as an assistant secretary of the U.S. Department of Veterans Affairs.

The district is politically divided: Democrats have a registration edge, even though Trump won it in 2016.

To a great extent, the campaign has focused on the usual grist of Pennsylvania’s elections: the state’s booming natural gas industry, abortion rights, gun rights, jobs and the minimum wage.

Then there’s the TV attack ad by Raja that tries to link Iovino to the Green New Deal, a wide-ranging plan to combat climate change supported by several Democratic members of Congress.

The ad says Iovino has “teamed up with extremists who want to stop our growth with billions in new energy taxes” and fans out photos of prominent Democrats, including House Speaker Nancy Pelosi of California, Vermont Sen. Bernie Sanders and New York Rep. Alexandria Ocasio-Cortez.

Republican strategists hope to see extra energy from their party’s base amid a backlash to the Green New Deal and what a Raja campaign strategist called special counsel Robert Mueller’s “overreach.”

“The things that motivate Republicans tend to be national issues,” said Ray Zaborney, the strategist.

Iovino’s campaign said she has no position on the Green New Deal and has not spoken in support of it.

“They’re trying to nationalize Pam because there is no dirt on her,” said Iovino campaign strategist David Marshall.